this post seemed helpful as well
https://forums.rpgmakerweb.com/index.php?threads/need-some-help-cannot-open-a-ga...
Update:
Using the command <sudo chmod -R 755 Game.app> allows the game to run, which is progress.
However,I now get this:
My current file path is downloads/CrystalDesiresMac1.02/CrystalDesires/Game.app
The folder CrystalDesires contains Game.app, v8_context_snapshot.x86_64.bin, and credits.html, which is how it came when I unzipped it.
Is there still something I'm missing?