Struggling to play on Mac OS X 10.7.5

Hi!

I'm trying to set up Wrath on a late 2006 iMac, running Mac OS X 10.7.5. Back when Cata came out, I was able to run Retail on a Macbook running 10.6.8, so I feel like it should work on my iMac?

At first I couldn't even get the application to open, but after perusing a few threads here (and googling), I've gotten the game to open, play the opening cinematic, and get to the login screen, which is where my current issue is, I try to log in and get this screen: [screencap]

I added WoW to my firewall, I just am not sure what else to do. :(