diff --git a/crates/bevy_gltf_blueprints/src/lib.rs b/crates/bevy_gltf_blueprints/src/lib.rs
index 366f05f..a89619c 100644
--- a/crates/bevy_gltf_blueprints/src/lib.rs
+++ b/crates/bevy_gltf_blueprints/src/lib.rs
@@ -120,6 +120,10 @@ impl Plugin for BlueprintsPlugin {
         .register_type::<MaterialInfo>()
         .register_type::<SpawnHere>()
         .register_type::<Animations>()
+        .register_type::<BlueprintsList>()
+        .register_type::<Vec<String>>()
+        .register_type::<HashMap<String,Vec<String>>>()
+        
         .insert_resource(BluePrintsConfig {
             format: self.format,
             library_folder: self.library_folder.clone(),
@@ -140,11 +144,29 @@ impl Plugin for BlueprintsPlugin {
         .add_systems(
             Update,
             (
-                spawn_from_blueprints,
-                compute_scene_aabbs.run_if(aabbs_enabled),
-                apply_deferred.run_if(aabbs_enabled),
+                ( 
+                    prepare_blueprints,
+                    check_for_loaded,
+                    spawn_from_blueprints, 
+                    apply_deferred
+                )
+                    .chain(),
+                (
+                    compute_scene_aabbs,
+                    apply_deferred
+                )
+                    .chain()
+                    .run_if(aabbs_enabled),
+
                 apply_deferred,
-                materials_inject.run_if(materials_library_enabled),
+                
+                (
+                    materials_inject,
+                    check_for_material_loaded,
+                    materials_inject2
+                )
+                    .chain()
+                    .run_if(materials_library_enabled),
             )
                 .chain()
                 .in_set(GltfBlueprintsSet::Spawn),
diff --git a/crates/bevy_gltf_blueprints/src/materials.rs b/crates/bevy_gltf_blueprints/src/materials.rs
index 5f0140a..f8f5e26 100644
--- a/crates/bevy_gltf_blueprints/src/materials.rs
+++ b/crates/bevy_gltf_blueprints/src/materials.rs
@@ -1,22 +1,19 @@
 use std::path::Path;
 
 use bevy::{
-    asset::{AssetServer, Assets, Handle},
+    asset::{AssetId, AssetServer, Assets, Handle},
     ecs::{
-        component::Component,
-        query::{Added, With},
-        reflect::ReflectComponent,
-        system::{Commands, Query, Res, ResMut},
+        component::Component, entity::Entity, query::{Added, With}, reflect::ReflectComponent, system::{Commands, Query, Res, ResMut}
     },
     gltf::Gltf,
     hierarchy::{Children, Parent},
-    log::debug,
+    log::{debug, info},
     pbr::StandardMaterial,
     reflect::Reflect,
     render::mesh::Mesh,
 };
 
-use crate::BluePrintsConfig;
+use crate::{AssetLoadTracker, AssetsToLoad, BluePrintsConfig};
 
 #[derive(Component, Reflect, Default, Debug)]
 #[reflect(Component)]
@@ -26,10 +23,105 @@ pub struct MaterialInfo {
     pub source: String,
 }
 
+/// flag component
+#[derive(Component)]
+pub(crate) struct BlueprintMaterialAssetsLoaded;
+/// flag component
+#[derive(Component)]
+pub(crate) struct BlueprintMaterialAssetsNotLoaded;
+
 /// system that injects / replaces materials from material library
 pub(crate) fn materials_inject(
+    blueprints_config: ResMut<BluePrintsConfig>,
+    material_infos: Query<(Entity, &MaterialInfo), Added<MaterialInfo>>,
+    asset_server: Res<AssetServer>,
+    mut commands: Commands,
+) {
+    for (entity, material_info) in material_infos.iter() {
+        let model_file_name = format!(
+            "{}_materials_library.{}",
+            &material_info.source, &blueprints_config.format
+        );
+        let materials_path = Path::new(&blueprints_config.material_library_folder)
+            .join(Path::new(model_file_name.as_str()));
+        let material_name = &material_info.name;
+        let material_full_path = materials_path.to_str().unwrap().to_string() + "#" + material_name; // TODO: yikes, cleanup
+
+        if blueprints_config
+            .material_library_cache
+            .contains_key(&material_full_path)
+        {
+            debug!("material is cached, retrieving");
+            blueprints_config
+                .material_library_cache
+                .get(&material_full_path)
+                .expect("we should have the material available");
+            commands
+                .entity(entity)
+                .insert(BlueprintMaterialAssetsLoaded);
+
+        } else {
+            let material_file_handle: Handle<Gltf> = asset_server.load(materials_path.clone());
+            let material_file_id = material_file_handle.id();
+            let mut asset_infos:Vec<AssetLoadTracker<Gltf>> = vec![];
+
+            asset_infos.push(AssetLoadTracker {
+                name: material_full_path,
+                id: material_file_id,
+                loaded: false,
+                handle: material_file_handle.clone()
+            });
+            commands
+                .entity(entity)
+                .insert(AssetsToLoad{
+                    all_loaded: false,
+                    asset_infos: asset_infos,
+                    progress: 0.0
+                    //..Default::default()
+                })
+                .insert(BlueprintMaterialAssetsNotLoaded);
+            /**/
+        }
+    }
+}
+
+// TODO, merge with check_for_loaded, make generic ?
+pub(crate) fn check_for_material_loaded(
+    mut blueprint_assets_to_load: Query<(Entity, &mut AssetsToLoad<Gltf>),With<BlueprintMaterialAssetsNotLoaded>>,
+    asset_server: Res<AssetServer>,
+    mut commands: Commands,
+){
+    for (entity, mut assets_to_load) in blueprint_assets_to_load.iter_mut(){
+        let mut all_loaded = true;
+        let mut loaded_amount = 0;
+        let total = assets_to_load.asset_infos.len();
+        for tracker in assets_to_load.asset_infos.iter_mut(){
+            let asset_id = tracker.id;
+            let loaded = asset_server.is_loaded_with_dependencies(asset_id);
+            tracker.loaded = loaded;
+            if loaded {
+                loaded_amount += 1;
+            }else{
+                all_loaded = false;
+            }
+        }
+        let progress:f32 = loaded_amount as f32 / total as f32;
+        assets_to_load.progress = progress;
+
+        if all_loaded {
+            assets_to_load.all_loaded = true;
+            commands.entity(entity)
+                .insert(BlueprintMaterialAssetsLoaded)
+                .remove::<BlueprintMaterialAssetsNotLoaded>();
+        }
+    }
+}
+
+
+/// system that injects / replaces materials from material library
+pub(crate) fn materials_inject2(
     mut blueprints_config: ResMut<BluePrintsConfig>,
-    material_infos: Query<(&MaterialInfo, &Children), Added<MaterialInfo>>,
+    material_infos: Query<(&MaterialInfo, &Children, ), (Added<BlueprintMaterialAssetsLoaded>, With<BlueprintMaterialAssetsLoaded>)>,
     with_materials_and_meshes: Query<
         (),
         (
@@ -38,9 +130,9 @@ pub(crate) fn materials_inject(
             With<Handle<Mesh>>,
         ),
     >,
-    models: Res<Assets<bevy::gltf::Gltf>>,
-
+    assets_gltf: Res<Assets<Gltf>>,
     asset_server: Res<AssetServer>,
+
     mut commands: Commands,
 ) {
     for (material_info, children) in material_infos.iter() {
@@ -65,10 +157,10 @@ pub(crate) fn materials_inject(
                 .get(&material_full_path)
                 .expect("we should have the material available");
             material_found = Some(material);
-        } else {
-            let my_gltf: Handle<Gltf> = asset_server.load(materials_path.clone());
-            let mat_gltf = models
-                .get(my_gltf.id())
+        }else {
+            let model_handle: Handle<Gltf> = asset_server.load(materials_path.clone());// FIXME: kinda weird now 
+            let mat_gltf = assets_gltf
+                .get(model_handle.id())
                 .expect("material should have been preloaded");
             if mat_gltf.named_materials.contains_key(material_name) {
                 let material = mat_gltf
diff --git a/crates/bevy_gltf_blueprints/src/spawn_from_blueprints.rs b/crates/bevy_gltf_blueprints/src/spawn_from_blueprints.rs
index 3701fa5..8603479 100644
--- a/crates/bevy_gltf_blueprints/src/spawn_from_blueprints.rs
+++ b/crates/bevy_gltf_blueprints/src/spawn_from_blueprints.rs
@@ -1,6 +1,6 @@
 use std::path::{Path, PathBuf};
 
-use bevy::{gltf::Gltf, prelude::*};
+use bevy::{gltf::Gltf, prelude::*, utils::HashMap};
 
 use crate::{Animations, BluePrintsConfig};
 
@@ -46,22 +46,169 @@ pub struct AddToGameWorld;
 /// helper component, just to transfer child data
 pub(crate) struct OriginalChildren(pub Vec<Entity>);
 
-/// main spawning functions,
+#[derive(Component, Reflect, Default, Debug)]
+#[reflect(Component)]
+pub struct BlueprintsList(pub HashMap<String,Vec<String>>);
+
+#[derive(Default, Debug)]
+pub(crate) struct AssetLoadTracker<T:bevy::prelude::Asset>{
+    pub name: String,
+    pub id: AssetId<T>,
+    pub loaded: bool,
+    pub handle: Handle<T>
+}
+#[derive(Component, Default, Debug)]
+pub(crate) struct AssetsToLoad<T:bevy::prelude::Asset>{
+    pub all_loaded: bool,
+    pub asset_infos: Vec<AssetLoadTracker<T>>,
+    pub progress: f32
+}
+
+
+/// flag component
+#[derive(Component)]
+pub(crate) struct BlueprintAssetsLoaded;
+/// flag component
+#[derive(Component)]
+pub(crate) struct BlueprintAssetsNotLoaded;
+
+/// spawning prepare function,
 /// * also takes into account the already exisiting "override" components, ie "override components" > components from blueprint
-pub(crate) fn spawn_from_blueprints(
+pub(crate) fn prepare_blueprints(
     spawn_placeholders: Query<
         (
             Entity,
             &BlueprintName,
-            Option<&Transform>,
             Option<&Parent>,
             Option<&Library>,
-            Option<&AddToGameWorld>,
             Option<&Name>,
+            Option<&BlueprintsList>,
         ),
         (Added<BlueprintName>, Added<SpawnHere>, Without<Spawned>),
     >,
 
+    mut commands: Commands,
+    asset_server: Res<AssetServer>,
+    blueprints_config: Res<BluePrintsConfig>,
+) {
+    for (
+        entity,
+        blupeprint_name,
+        original_parent,
+        library_override,
+        name,
+
+        blueprints_list,
+    ) in spawn_placeholders.iter()
+    {
+        debug!(
+            "requesting to spawn {:?} for entity {:?}, id: {:?}, parent:{:?}",
+            blupeprint_name.0, name, entity, original_parent
+        );
+
+        // println!("main model path {:?}", model_path);
+        if blueprints_list.is_some() {
+            let blueprints_list = blueprints_list.unwrap();
+            // println!("blueprints list {:?}", blueprints_list.0.keys());
+            let mut asset_infos:Vec<AssetLoadTracker<Gltf>> = vec![];
+
+            for (blueprint_name, _) in blueprints_list.0.iter() {
+                /*if blueprint_name == what {
+                    println!("WHOLY MOLLY !")
+                }*/
+                // println!("library path {:?}", library_path);
+                let mut library_path = &blueprints_config.library_folder; // TODO: we cannot use the overriden library path
+                // FIXME: hack
+                if blueprint_name == "World" {
+                    library_path= &library_override.unwrap().0;
+                }
+
+                let model_file_name = format!("{}.{}", &blueprint_name, &blueprints_config.format);
+                let model_path = Path::new(&library_path).join(Path::new(model_file_name.as_str()));
+
+                let model_handle: Handle<Gltf> = asset_server.load(model_path.clone());
+                let model_id = model_handle.id();
+                let loaded = asset_server.is_loaded_with_dependencies(model_id);
+                if !loaded {
+                    asset_infos.push(AssetLoadTracker {
+                        name: model_path.to_string_lossy().into(),
+                        id: model_id,
+                        loaded: false,
+                        handle: model_handle.clone()
+                    })
+                }
+            }
+            // if not all assets are already loaded, inject a component to signal that we need them to be loaded
+            if asset_infos.len() > 0 {
+                commands
+                .entity(entity)
+                .insert(AssetsToLoad{
+                    all_loaded: false,
+                    asset_infos: asset_infos,
+                    progress: 0.0
+                    //..Default::default()
+                })
+                .insert(BlueprintAssetsNotLoaded);
+            }else {
+                commands
+                .entity(entity)
+                .insert(BlueprintAssetsLoaded);
+            }
+        }
+        else { // in case there are no blueprintsList
+            commands
+            .entity(entity)
+            .insert(BlueprintAssetsLoaded);
+        }
+    }
+}
+
+pub(crate) fn check_for_loaded(
+    mut blueprint_assets_to_load: Query<(Entity, &mut AssetsToLoad<Gltf>), With<BlueprintAssetsNotLoaded>>,
+    asset_server: Res<AssetServer>,
+    mut commands: Commands,
+){
+    for (entity, mut assets_to_load) in blueprint_assets_to_load.iter_mut(){
+        let mut all_loaded = true;
+        let mut loaded_amount = 0;
+        let total = assets_to_load.asset_infos.len();
+        for tracker in assets_to_load.asset_infos.iter_mut(){
+            let asset_id = tracker.id;
+            let loaded = asset_server.is_loaded_with_dependencies(asset_id);
+            tracker.loaded = loaded;
+            if loaded {
+                loaded_amount += 1;
+            }else{
+                all_loaded = false;
+            }
+        }
+        let progress:f32 = loaded_amount as f32 / total as f32;
+        // println!("progress: {}",progress);
+        assets_to_load.progress = progress;
+
+        if all_loaded {
+            assets_to_load.all_loaded = true;
+            commands.entity(entity)
+                .insert(BlueprintAssetsLoaded)
+                .remove::<BlueprintAssetsNotLoaded>();
+        }
+    }
+}
+
+pub(crate) fn spawn_from_blueprints(
+    spawn_placeholders: Query<
+    (
+        Entity,
+        &BlueprintName,
+        Option<&Transform>,
+        Option<&Parent>,
+        Option<&Library>,
+        Option<&AddToGameWorld>,
+        Option<&Name>,
+    ),
+    (With<BlueprintAssetsLoaded>, Added<BlueprintAssetsLoaded>, Without<BlueprintAssetsNotLoaded>),
+    >,
+
     mut commands: Commands,
     mut game_world: Query<Entity, With<GameWorldTag>>,
 
@@ -70,7 +217,8 @@ pub(crate) fn spawn_from_blueprints(
     blueprints_config: Res<BluePrintsConfig>,
 
     children: Query<&Children>,
-) {
+){
+
     for (
         entity,
         blupeprint_name,
@@ -79,20 +227,14 @@ pub(crate) fn spawn_from_blueprints(
         library_override,
         add_to_world,
         name,
+
     ) in spawn_placeholders.iter()
     {
-        debug!(
-            "need to spawn {:?} for entity {:?}, id: {:?}, parent:{:?}",
+        info!(
+            "attempting to spawn {:?} for entity {:?}, id: {:?}, parent:{:?}",
             blupeprint_name.0, name, entity, original_parent
         );
 
-        let mut original_children: Vec<Entity> = vec![];
-        if let Ok(c) = children.get(entity) {
-            for child in c.iter() {
-                original_children.push(*child);
-            }
-        }
-
         let what = &blupeprint_name.0;
         let model_file_name = format!("{}.{}", &what, &blueprints_config.format);
 
@@ -101,8 +243,8 @@ pub(crate) fn spawn_from_blueprints(
             library_override.map_or_else(|| &blueprints_config.library_folder, |l| &l.0);
         let model_path = Path::new(&library_path).join(Path::new(model_file_name.as_str()));
 
-        debug!("attempting to spawn {:?}", model_path);
-        let model_handle: Handle<Gltf> = asset_server.load(model_path);
+        // info!("attempting to spawn {:?}", model_path);
+        let model_handle: Handle<Gltf> = asset_server.load(model_path);// FIXME: kinda weird now 
 
         let gltf = assets_gltf
             .get(&model_handle)
@@ -123,6 +265,12 @@ pub(crate) fn spawn_from_blueprints(
             transforms = *transform.unwrap();
         }
 
+        let mut original_children: Vec<Entity> = vec![];
+        if let Ok(c) = children.get(entity) {
+            for child in c.iter() {
+                original_children.push(*child);
+            }
+        }
         commands.entity(entity).insert((
             SceneBundle {
                 scene: scene.clone(),
@@ -143,4 +291,4 @@ pub(crate) fn spawn_from_blueprints(
             commands.entity(world).add_child(entity);
         }
     }
-}
+}
\ No newline at end of file
diff --git a/crates/bevy_gltf_blueprints/src/spawn_post_process.rs b/crates/bevy_gltf_blueprints/src/spawn_post_process.rs
index 2caa625..db84f89 100644
--- a/crates/bevy_gltf_blueprints/src/spawn_post_process.rs
+++ b/crates/bevy_gltf_blueprints/src/spawn_post_process.rs
@@ -1,12 +1,13 @@
 use std::any::TypeId;
 
+use bevy::gltf::Gltf;
 use bevy::prelude::*;
 use bevy::scene::SceneInstance;
 // use bevy::utils::hashbrown::HashSet;
 
 use super::{AnimationPlayerLink, Animations};
 use super::{SpawnHere, Spawned};
-use crate::{CopyComponents, InBlueprint, NoInBlueprint, OriginalChildren};
+use crate::{AssetsToLoad, BlueprintAssetsLoaded, CopyComponents, InBlueprint, NoInBlueprint, OriginalChildren};
 
 /// this system is in charge of doing any necessary post processing after a blueprint scene has been spawned
 /// - it removes one level of useless nesting
@@ -89,6 +90,8 @@ pub(crate) fn spawned_blueprint_post_process(
         commands.entity(original).remove::<SpawnHere>();
         commands.entity(original).remove::<Spawned>();
         commands.entity(original).remove::<Handle<Scene>>();
+        commands.entity(original).remove::<AssetsToLoad<Gltf>>();// also clear the sub assets tracker to free up handles, perhaps just freeing up the handles and leave the rest would be better ?
+        commands.entity(original).remove::<BlueprintAssetsLoaded>();
         commands.entity(root_entity).despawn_recursive();
     }
 }
diff --git a/examples/bevy_gltf_blueprints/animation/src/game/in_game.rs b/examples/bevy_gltf_blueprints/animation/src/game/in_game.rs
index fcf711b..454ce27 100644
--- a/examples/bevy_gltf_blueprints/animation/src/game/in_game.rs
+++ b/examples/bevy_gltf_blueprints/animation/src/game/in_game.rs
@@ -30,7 +30,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/bevy_gltf_blueprints/basic/src/game/in_game.rs b/examples/bevy_gltf_blueprints/basic/src/game/in_game.rs
index 3af11d5..231137b 100644
--- a/examples/bevy_gltf_blueprints/basic/src/game/in_game.rs
+++ b/examples/bevy_gltf_blueprints/basic/src/game/in_game.rs
@@ -20,7 +20,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/bevy_gltf_blueprints/basic_xpbd_physics/src/game/in_game.rs b/examples/bevy_gltf_blueprints/basic_xpbd_physics/src/game/in_game.rs
index 3fa60da..6853655 100644
--- a/examples/bevy_gltf_blueprints/basic_xpbd_physics/src/game/in_game.rs
+++ b/examples/bevy_gltf_blueprints/basic_xpbd_physics/src/game/in_game.rs
@@ -20,7 +20,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/bevy_gltf_blueprints/materials/src/game/in_game.rs b/examples/bevy_gltf_blueprints/materials/src/game/in_game.rs
index e5fc8b8..6bdf1d9 100644
--- a/examples/bevy_gltf_blueprints/materials/src/game/in_game.rs
+++ b/examples/bevy_gltf_blueprints/materials/src/game/in_game.rs
@@ -21,7 +21,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/in_game.rs b/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/in_game.rs
index 75be98a..11ee36d 100644
--- a/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/in_game.rs
+++ b/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/in_game.rs
@@ -21,7 +21,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/level_transitions.rs b/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/level_transitions.rs
index 41d5c90..4dcb69c 100644
--- a/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/level_transitions.rs
+++ b/examples/bevy_gltf_blueprints/multiple_levels_multiple_blendfiles/src/game/level_transitions.rs
@@ -76,7 +76,7 @@ pub fn trigger_level_transition(
                     } else if target_level == "Level2" {
                         level = game_assets.level2.clone().unwrap();
                     } else {
-                        level = game_assets.world.clone();
+                        level = game_assets.world.clone().unwrap();
                     }
                     info!("spawning new level");
                     commands.spawn((
diff --git a/examples/bevy_registry_export/basic/src/game/in_game.rs b/examples/bevy_registry_export/basic/src/game/in_game.rs
index 75be98a..11ee36d 100644
--- a/examples/bevy_registry_export/basic/src/game/in_game.rs
+++ b/examples/bevy_registry_export/basic/src/game/in_game.rs
@@ -21,7 +21,7 @@ pub fn setup_game(
         SceneBundle {
             // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
             scene: models
-                .get(game_assets.world.id())
+                .get(game_assets.world.clone().unwrap().id())
                 .expect("main level should have been loaded")
                 .scenes[0]
                 .clone(),
diff --git a/examples/common/src/assets/assets_game.rs b/examples/common/src/assets/assets_game.rs
index 988e964..5bb5986 100644
--- a/examples/common/src/assets/assets_game.rs
+++ b/examples/common/src/assets/assets_game.rs
@@ -5,8 +5,8 @@ use bevy_asset_loader::prelude::*;
 
 #[derive(AssetCollection, Resource)]
 pub struct GameAssets {
-    #[asset(key = "world")]
-    pub world: Handle<Gltf>,
+    #[asset(key = "world", optional)]
+    pub world: Option<Handle<Gltf>>,
 
     #[asset(key = "world_dynamic", optional)]
     pub world_dynamic: Option<Handle<Gltf>>,
@@ -16,8 +16,8 @@ pub struct GameAssets {
     #[asset(key = "level2", optional)]
     pub level2: Option<Handle<Gltf>>,
 
-    #[asset(key = "models", collection(typed, mapped))]
-    pub models: HashMap<String, Handle<Gltf>>,
+    #[asset(key = "models", collection(typed, mapped), optional)]
+    pub models: Option<HashMap<String, Handle<Gltf>>>,
 
     #[asset(key = "materials", collection(typed, mapped), optional)]
     pub materials: Option<HashMap<String, Handle<Gltf>>>,
diff --git a/testing/bevy_example/assets/assets_game.assets.ron b/testing/bevy_example/assets/assets_game.assets.ron
index 5b1e969..40825c0 100644
--- a/testing/bevy_example/assets/assets_game.assets.ron
+++ b/testing/bevy_example/assets/assets_game.assets.ron
@@ -1,6 +1,6 @@
 ({
-    "world":File (path: "models/World.glb"),
+    /*"world":File (path: "models/World.glb"),
     "models": Folder (
         path: "models/library",
-    ),
+    ),*/
 })
\ No newline at end of file
diff --git a/testing/bevy_example/src/core/mod.rs b/testing/bevy_example/src/core/mod.rs
index 1ef7f3e..7c16989 100644
--- a/testing/bevy_example/src/core/mod.rs
+++ b/testing/bevy_example/src/core/mod.rs
@@ -11,6 +11,7 @@ impl Plugin for CorePlugin {
                 legacy_mode: false,
                 library_folder: "models/library".into(),
                 format: GltfFormat::GLB,
+                material_library:true,
                 aabbs: true,
                 ..Default::default()
             },
diff --git a/testing/bevy_example/src/game/in_game.rs b/testing/bevy_example/src/game/in_game.rs
index 75be98a..03ecb47 100644
--- a/testing/bevy_example/src/game/in_game.rs
+++ b/testing/bevy_example/src/game/in_game.rs
@@ -1,5 +1,5 @@
-use bevy::prelude::*;
-use bevy_gltf_blueprints::{BluePrintBundle, BlueprintName, GameWorldTag};
+use bevy::{prelude::*, utils::hashbrown::HashMap};
+use bevy_gltf_blueprints::{BluePrintBundle, BlueprintName, BlueprintsList, GameWorldTag, Library, SpawnHere};
 use bevy_gltf_worlflow_examples_common_rapier::{assets::GameAssets, GameState, InAppRunning};
 
 use bevy_rapier3d::prelude::Velocity;
@@ -7,31 +7,19 @@ use rand::Rng;
 
 pub fn setup_game(
     mut commands: Commands,
-    game_assets: Res<GameAssets>,
-    models: Res<Assets<bevy::gltf::Gltf>>,
+    asset_server: Res<AssetServer>,
     mut next_game_state: ResMut<NextState<GameState>>,
 ) {
-    commands.insert_resource(AmbientLight {
-        color: Color::WHITE,
-        brightness: 0.2,
-    });
     // here we actually spawn our game world/level
-
     commands.spawn((
-        SceneBundle {
-            // note: because of this issue https://github.com/bevyengine/bevy/issues/10436, "world" is now a gltf file instead of a scene
-            scene: models
-                .get(game_assets.world.id())
-                .expect("main level should have been loaded")
-                .scenes[0]
-                .clone(),
+        SceneBundle{
+            scene: asset_server.load("models/World.glb#Scene0"),
             ..default()
         },
         bevy::prelude::Name::from("world"),
         GameWorldTag,
         InAppRunning,
     ));
-
     next_game_state.set(GameState::InGame)
 }
 
diff --git a/testing/bevy_example/src/game/mod.rs b/testing/bevy_example/src/game/mod.rs
index 99b9b3f..d537091 100644
--- a/testing/bevy_example/src/game/mod.rs
+++ b/testing/bevy_example/src/game/mod.rs
@@ -97,13 +97,15 @@ impl Plugin for GamePlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(Update, (spawn_test).run_if(in_state(GameState::InGame)))
             .add_systems(Update, validate_export)
-            .add_systems(Update, generate_screenshot.run_if(on_timer(Duration::from_secs_f32(0.2)))) // TODO: run once
             .add_systems(OnEnter(AppState::MenuRunning), start_game)
             .add_systems(OnEnter(AppState::AppRunning), setup_game)
+            /*             .add_systems(Update, generate_screenshot.run_if(on_timer(Duration::from_secs_f32(0.2)))) // TODO: run once
+
+            
             .add_systems(
                 Update,
                 exit_game.run_if(on_timer(Duration::from_secs_f32(0.5))),
-            ) // shut down the app after this time
+            ) // shut down the app after this time*/
             ;
     }
 }
diff --git a/tools/gltf_auto_export/auto_export/export_main_scenes.py b/tools/gltf_auto_export/auto_export/export_main_scenes.py
index 8bdb018..25cfd37 100644
--- a/tools/gltf_auto_export/auto_export/export_main_scenes.py
+++ b/tools/gltf_auto_export/auto_export/export_main_scenes.py
@@ -4,7 +4,7 @@ import bpy
 from ..helpers.generate_and_export import generate_and_export
 from .export_gltf import (generate_gltf_export_preferences, export_gltf)
 from ..modules.bevy_dynamic import is_object_dynamic, is_object_static
-from ..helpers.helpers_scenes import clear_hollow_scene, copy_hollowed_collection_into
+from ..helpers.helpers_scenes import clear_hollow_scene, copy_hollowed_collection_into, inject_blueprints_list_into_main_scene
 
 
 # export all main scenes
@@ -29,6 +29,8 @@ def export_main_scene(scene, folder_path, addon_prefs, library_collections):
                        }
 
     if export_blueprints : 
+        inject_blueprints_list_into_main_scene(scene)
+
         if export_separate_dynamic_and_static_objects:
             #print("SPLIT STATIC AND DYNAMIC")
             # first export static objects
diff --git a/tools/gltf_auto_export/helpers/helpers_collections.py b/tools/gltf_auto_export/helpers/helpers_collections.py
index edb3214..a1cd927 100644
--- a/tools/gltf_auto_export/helpers/helpers_collections.py
+++ b/tools/gltf_auto_export/helpers/helpers_collections.py
@@ -36,16 +36,23 @@ def get_marked_collections(scene, addon_prefs):
     return (collection_names, marked_collections)
 
 # gets all collections within collections that might also be relevant
-def get_sub_collections(collections, parent, children_per_collection):
+def get_sub_collections(collections, parent=None, children_per_collection=None):
+    if parent == None:
+        parent = CollectionNode()
+    if children_per_collection == None:
+        children_per_collection = {}
+
     collection_names = set()
     used_collections = []
     
     for root_collection in collections:
-        node = Node(name=root_collection.name, parent=parent)
+        print("collections", collections)
+        node = CollectionNode(name=root_collection.name, parent=parent)
         parent.children.append(node)
 
         #print("root collection", root_collection.name)
         for collection in traverse_tree(root_collection): # TODO: filter out COLLECTIONS that have the flatten flag (unlike the flatten flag on colleciton instances themselves)
+            print("sub", collection)
             node_name = collection.name
             children_per_collection[node_name] = []
             #print("  scanning", collection.name)
@@ -53,12 +60,17 @@ def get_sub_collections(collections, parent, children_per_collection):
                 #print("FLATTEN", object.name, 'Flatten' in object)
                 if object.instance_type == 'COLLECTION' : # and not 'Flatten' in object: 
                     collection_name = object.instance_collection.name
+                    print("sub obj", collection_name)
+                    # FIXME: not sure:
+                    children_per_collection[node_name].append(collection_name)
+
                     (sub_names, sub_collections) = get_sub_collections([object.instance_collection], node, children_per_collection)
+                    print("gna", sub_names, sub_collections)
                     if len(list(sub_names)) > 0:
+                        print("toto")
                         children_per_collection[node_name]  += (list(sub_names))
                     #print("   found sub collection in use", object.name, object.instance_collection)
 
-
                     if not collection_name in collection_names: 
                         collection_names.add(collection_name)
                         used_collections.append(object.instance_collection)
@@ -77,7 +89,7 @@ def flatten_collection_tree(node, children_per_collection):
     children_per_collection[node.name] = list(set( children_per_collection[node.name]))
        
 
-class Node :
+class CollectionNode :
     def __init__(self, name="", parent=None):
       self.name = name
       self.children = []
@@ -93,7 +105,7 @@ def get_exportable_collections(main_scenes, library_scenes, addon_prefs):
 
     all_collections = []
     all_collection_names = []
-    root_node = Node()
+    root_node = CollectionNode()
     root_node.name = "root"
     children_per_collection = {}
 
diff --git a/tools/gltf_auto_export/helpers/helpers_scenes.py b/tools/gltf_auto_export/helpers/helpers_scenes.py
index e5b4dfb..5d49357 100644
--- a/tools/gltf_auto_export/helpers/helpers_scenes.py
+++ b/tools/gltf_auto_export/helpers/helpers_scenes.py
@@ -1,5 +1,6 @@
+import json
 import bpy
-from .helpers_collections import (set_active_collection)
+from .helpers_collections import (CollectionNode, get_sub_collections, get_used_collections, set_active_collection)
 from .object_makers import (make_empty)
 
 
@@ -149,3 +150,40 @@ def get_scenes(addon_prefs):
     return [level_scene_names, level_scenes, library_scene_names, library_scenes]
 
 
+
+
+def inject_blueprints_list_into_main_scene(scene):
+    print("injecting assets data")
+    root_collection = scene.collection
+    assets_list = None
+    for object in scene.objects:
+        if object.name == "assets_list"+scene.name:
+            assets_list = object
+            break
+
+    if assets_list is None:
+        assets_list = make_empty('assets_list_'+scene.name, [0,0,0], [0,0,0], [0,0,0], root_collection)
+
+
+    # find all blueprints used in a scene
+    # TODO: export a tree rather than a flat list ? because you could have potential clashing items in flat lists (amongst other issues)
+    (collection_names, collections) = get_used_collections(scene)
+    root_node = CollectionNode()
+    root_node.name = "root"
+    children_per_collection = {}
+    
+    #print("collection_names", collection_names, "collections", collections)
+    (bla, bli ) = get_sub_collections(collections, root_node, children_per_collection)
+    #print("sfdsfsdf", bla, bli, "root", root_node, "children_per_collection", children_per_collection)
+    # with sub collections
+    #    (collection_names, collections) = get_sub_collections(all_collections, root_node, children_per_collection)
+    #
+    # what about marked assets ?
+    #assets_list["blueprints_direct"] = list(collection_names)
+    assets_list["BlueprintsList"] = f"({json.dumps(dict(children_per_collection))})"
+    #'({"a":[]})'
+    #'([])'
+    #
+    #
+
+    print("assets list", assets_list["BlueprintsList"], children_per_collection)
diff --git a/tools/gltf_auto_export/tests/test_bevy_integration.py b/tools/gltf_auto_export/tests/test_bevy_integration.py
index afd5255..d91c148 100644
--- a/tools/gltf_auto_export/tests/test_bevy_integration.py
+++ b/tools/gltf_auto_export/tests/test_bevy_integration.py
@@ -20,7 +20,7 @@ def setup_data(request):
         #other_materials_path = os.path.join("../../testing", "other_materials")
 
         print("\nPerforming teardown...")
-        if os.path.exists(models_path):
+        '''if os.path.exists(models_path):
             shutil.rmtree(models_path)
 
         """if os.path.exists(materials_path):
@@ -34,7 +34,7 @@ def setup_data(request):
 
         screenshot_observed_path = os.path.join(root_path, "screenshot.png")
         if os.path.exists(screenshot_observed_path):
-            os.remove(screenshot_observed_path)
+            os.remove(screenshot_observed_path)'''
 
     request.addfinalizer(finalizer)