I cannot new game the official version but I can do this in demo.I'm on MacOS
Try installing the game with the Itch app: https://itch.io/app
Once you have done that you can move your save files from the demo into the full game if you don't want to start over from the beginning
Yes, installing it from the Itch app fixes all file permission crashes in the Mac version of the game. There are other ways to fix it too, but the app install method is the most consistent fix. If you have further problems, please let us know! We also have an active Discord community where other players would also be happy to help you :)