update

scripts/main.gd

@@ -24,8 +24,9 @@ func _unhandled_key_input(event: InputEvent) -> void:
 func _start_game(cfg: Dictionary) -> void:
 	if game != null:
 		return
-	menu.queue_free()
-	menu = null
+	if menu != null:
+		menu.queue_free()
+		menu = null
 	game = Node3D.new()
 	game.set_script(preload("res://scripts/game.gd"))
 	game.name = "Game"   # fester Pfad, sonst findet das RPC-Routing den Knoten nicht