This worked, thank you! Though I did need to also run:
sudo chmod -R 755 path/to/app.app
In order to open it on Big Sur
Also while you're here, just a small accessibility feature request should you ever get the chance or feel the mood hit. I'm ridiculously disabled and play games with one hand. The fact that you have rebinding is absolutely wonderful, but having the added ability to assign commands to the mouse clicks would be exceeding useful.
Amazing game and thank you for responding