Aha. In that case, the only thing I can suggest (if such a thing is possible on a Mac) is to create a batch file or the Mac equivalent that would delete the cache file and then launch the game.
I don't know how to create a batch file, I'm no programmer. Are there any tutorials for that? (Easy ones)
I could tell you how on a Windows rig, but unfortunately I don't know the first thing about Macintosh. I did find out via Google that the term for Macs would be a "shell script" rather than "batch file," so all I can suggest is you poke around some Mac forums and see if anyone can help you out. Good luck!