Heya! So, got another piece of advice from another game on this site about Mac Catalina users. Go to the Mac game file that I said in my instructions, inside the package contents, and open Terminal. Type 'cmod +x' and tap space to leave a gap. Then, drag the MacOS game file onto the end of the command and it should create a file path. Activate that command, and it should start the game no problem. If this doesn't work, try downloading the game again and trying it on an unaltered version. Hopefully this helps.