upd

manifest.json

@@ -4,6 +4,7 @@
   "version": "1.0.0",
   "author": "ct",
   "description": "Development tools",
+  "category": "tools",
   "sources": [
     "src/**/*.cs"
   ],

src/ScenarioEditor/ScenarioEditorWindow.cs

@@ -324,7 +324,7 @@ namespace Cthangover.Core.UI.Tool.ScenarioEditor
             }
 
             var sceneService = GetNodeOrNull<GodotSceneService>("/root/GodotSceneService");
-            sceneService?.LoadScene("res://scenes/ui/base_scene.tscn");
+            sceneService?.LoadShell();
 
             _playActive = true;
         }