I'd pop open the bundle (right click it and choose "Show Package Contents") and just look around for some plain text configuration files that you can change to unlock stuff, if that's what you're looking for. Alternatively, such files may be in a folder labeled Preferences.
That data may be stored in non-plain text file though, which would make it difficult to figure out what the file does. In that case, there's no particularly easy way for a non-coder to figure this out. If you'd like to tackle it, feel free to become really good at understanding the language the game is written in (likely C++, Obj-C, or Java... there's a good chance the Wikipedia page will tell you which) and learn how to disassemble the game and run it in a debugger. Once you have it running in a debugger, if you can identify the variables, you can change them and unlock whatever you want.