Hi
Do you have any mods or CC? If you do, remove them for now and see if your Launcher will open. It could be that there are some conflicting mods/CC that are not compatible with the later patches.
If you don't have mods, or if taking them out doesn't fix the issue, then you may just be struck by the unknown error that often plagues Mac simmers. There's a few things you can try, though.
First of all, are you sure that your downloads of ITF and Ambitions were successfully installed? Is both your TS3 game and your Origin patched up to date? Your game should be at 1.63.
Do you manually reset the RAM when you are playing TS3? I had a lot of crashes on my iMac before I started doing this and sometimes couldn't get past opening the Launcher. Then I started monitoring the RAM usage and realised that just opening the Launcher was using a huge amount of memory. By resetting this before pressing play, I am now able to play. BluebellFlora has instructions on her website that you can use:
http://bluebellflora.com/the-sims-3-on-a-mac/resetting-ram-during-gameplay/
Let us know how you are getting on. There are a few other ideas in this help thread, which I would recommend reading as well:
http://answers.ea.com/t5/The-Sims-3/Links-to-Mac-help-threads-and-guides/m-p/749664#U749664
Caspin
