I'm not really a programmer by trade, I'm actually an artist XD as a result I'm not sure what could be a bug in the engine and whats me being crappy at programming haha
The biggest problem Godot has is a lot of the tutorials or answered questions online are for older versions of Godot and a lot of old functions have been renamed, merged with others, or just removed for better options so often you end up having to fix things the tutorial would have been totally correct about a year ago XD
I'm super excited to see how your project is looking by the way! :D I bet it's awesome! Keep at it!