Sims 3 CRASHES

Hi, I'm a mac user and I've recently installed all of the expansion packs (no stuff packs) and applied the ultimate fix according to the instructions as well. The game runs fine until it crashes every time within 3 mins of starting the game. It also gives me an error message saying 'unable to process' or somthing.. but if I ignore that, I can still play the game though it crashes soon like I said before. Is anyone having this sort of problem?

p.s I got the base game from another uploader and the expansion packs from games4theworld. Had problems with games4theworld base game and the whole thing didn't run until I uninstalled everything and installed the base game by another uploader.