All I'm asking you to do is run Generate FNIS for Users.exe through your MO2, click Update Behaviour (I think that's what the big button says), and copy/paste the text shown in the window afterwards. If your FNIS is throwing an actual error, make sure you've set it up properly ...
While trying to work on making the project Linux native I realized something and made this issue on proton (explained in issue)ValveSoftware/Proton#2670and because of that I've decided to delete the fork I made since as far as I can tell it would only benefit native Linux games. ...