johnki: Question, since this is the most relevant place I can think to ask: I see a lot on WineHQ about testing the Steam versions. How exactly does that work? Steam won't even let me download the PC version to a Mac. And then there's the issue of verification. Do people just install Steam into a Wineskin or something and download it from Steam THROUGH the Wineskin?
Since nobody had make an reply to your question, I'll try to answer you. Install Wineskin Winery and then download a reasonable stable wine engine into winery, eg wine 1.4.1; create a new wineskin wrapper.
Inside the wineskin wrapper, use winetricks to enable steam.
Launch steam as an application, wait for steam to complete its updating & setup your steam account.
Logon to your account & initiate installation of your steam game.
Edit: forgot to mention the need to wait for steam to complete its updating