I have to report a similar issue. I'm running 10.8.5 on my Mac Pro w/ dual monitors.
Full Screen won't work so I had to hit Command-F several times to get a flickering Options screen. I was eventually able to get to the Graphics options, lower my resolution to 1280x720 and play fine within a window. To test, I quit the game, restarted, and it still comes up within a window.
I wasn't in the beta but have heard nothing but great things about this game. Decided to give it a try and almost regretted it when this graphics issue came up. Hopefully a fix/patch will be forthcoming.