Slightly off-topic. But since the lack of achievements and the fact that I couldn't tab out of the game or play the audio through my TV (HDMI audio doesn't work on the Mac build, for some reason) really bugged me, I have now switched to the Windows version using Wineskin.
If anyone is interested, I would be happy to write a guide.
It's not too complicated and you're essentially trading graphical fidelity (the resulting "port" won't have reflections, so mirrors are basically brick walls mounted to other brick walls) and performance (it's considerably slower, but still playable. I'd say, 30-45 FPS) for feature parity (achievements -- though no Steam overlay* -- HDMI audio, etc).
Existing save games can be imported too, as long as they're from the base game and not AW.
*I currently research patching imm32.dll for this