How to get Wotlk on Mac???

Hey there, i've been trying to help my girlfriend get the server up and running on her mac. I followed the guide that Warmane, has posted. When I click on the Wow.exe in the folder, it says "Application cannot be opened." I went into her settings and check "Allow downloaded applications" to see if that worked, and nothing happened. The realmlist is correct, and all files are in the folder... Any idea on what to do? The guide is a bit confusing, when it comes to not allowing the game to update... Can anyone give me a easier to follow guide, or does anyone know a fix to this? I appreciate the help :)