Fullscreen broken in OS X 10.6.8 / Snow Leopard

[temhawk]

Amnesia works fine if I run it in windowed mode, but if I tick the "Fullscreen" option the game starts and becomes "invisible", so that I am able to see my desktop and hear the audio but there is just no picture, so I have to force quit.

This is at native resolution (1920x1200) by the way, and if I choose a lower resolution I can see the game, but it's not up-scaled and in the bottom-left corner of the screen, and it's still broken because if I move the cursor and click around parts of my desktop become visible and flicker.

In Lion fullscreen works, but I'd like to play the game in Snow Leopard (10.6.8).

My mac is:
17-inch MacBook Pro Late 2011
2.4 GHz Intel Core i7
8 GB 1333 MHz DDR3
1GB AMD Radeon HD 6770M

I am running Amnesia 1.2.1 of course.