Posted in off topic so it doesn't get buried in games.
I'm on my mac atm because my laptop is being dumb, so I go to steam, try to start Gmod, and it just doesn't start. The little hl2_osx application appears in the dock and on the little bar thingy on top, but the game doesn't start. It just stays on my desktop, forcing me to force quit the application. I filed a support ticket, but they haven't responded. Please halp :c It worked before this D: