I found the prefs.prop file, opened it and deleted everything inside it, saved it, and opened the game. At first it came up with an error message and asked if I wanted to try loading it again, I did and the game started up properly (for the first time in months). Although now I'm not getting any audio. I even closed the games (after adjusting screen settings) and then deleted the prefs.prop file entirely, when I reloaded the game, it remembered my screen settings and still had no audio, and had created another prefs.prop file (presumably it stores the preferences in another location too, but if the original exists then it overwrites the hidden preferences).
Can anyone help me get my audio back, or provide me with a clean prefs.prop file for a MacBook Pro?