University just stops loading. Better not be yet another EP I've bought and cannot play....

Ok EA, this is getting ridiculous....

This time, the problem is with University. I have been playing it since it came out, no problems, and then yesterday I tried to send another of my sims off to University. The university world loading screen loads fine and I can see the green bar going up at a steady rate, but then once it reaches about 0.5cm from the end, it just stops moving. It's not frozen because the little "tips" keep coming up and the music keeps playing. I have restarted, removed all custom content (of which I didn't have much in the first place), but nothing works. It always just stops in that same exact spot and goes no further.

I am honestly feeling really fed up if this is yet another EP I have bought and cannot play. I also have Supernatural and Seasons, both of which I have not been able to play on account of the amount of times they crash on me, it's not worth playing them. So, if University doesn't work, that's a total of over $200 I have effectively sent down the toilet.

I play on a year old iMac with OS X Lion with 3.1GHz Intel Core i5 and 4GB 1333 MHz DDR3. My graphics card is AMD Radeon HD 6970M 1024 MB.

I can run the full adobe suite, edit huge image files and video no problems. If I can do that, I should be able to run the Sims. 

Please, does anyone have any idea what is causing this??

Thank you so much for any suggestions!