Garry's Mod Blue Screen

Whenever I start up Garry’s Mod, it brings up a light blue screen that says “Loading…” In the bottom right corner. After 15 minutes, it crashes with no error report. Could you please help? I’m running a Mac 10.5.8

Garrys Mod is compatible with Mac OSX 10.6.8+

But when I look at the store page it says 10.5.8

The strange thing is though, I could run it perfectly and it would never crash. It started doing this out of nowhere. If I needed a higher version of Mac, I would get a message saying. "This is not compatible with your version.

Have you tried?
-Validating game?
-Delete Local Game content?

Yea a million times