Client not opening on Mac

Hey guys, been a long time since I've played and I bet the answer to my question might be around here already.

When opening the "World of Warcraft" application, I get the error message: "The application “World of Warcraft” can’t be opened.".

I'm guessing it could have something to do with the torrent (I downloaded it from Warmane). But it could totally be something else.

Could someone point me in the direction of the post that deals with this issue if it exists? (Or explain how to make it work)

http://forum.warmane.com/showthread....wnloaded-files