Editor slight refactor

addons/pvzadventure/scripts/adventure-editor/AdventureEditor.cs

@@ -57,6 +57,7 @@ public partial class AdventureEditor : MarginContainer
 	}
 	public void Play()
 	{
+		if (ResourceLoader.Exists(editedPath) == false) return;
 		var player = new AdventurePlayer();
 		var packed = new PackedScene();
 		player.pathToLevel = editedPath;