After installing Alan Wake (Humble Bundle version - can't confirm for other sources e.g. Steam or GOG.com) I kept getting an error popup referring to "CREATE_VERTEX_SHADER_ERROR". Turns out GLSL for shaders is not enabled by default. Enable it using this tutorial and the game will run, albeit slowly and without sound for now:
http://www.codeweavers.com/support/wiki/mac/mactutorial/registry_keys
Any tips on how to fix the sound please let me know! I have sound in the main menu and in cutscenes but not in the actual game.