I just installed Mountain Lion on my 12-core Mac Pro, did a clean install of CS6 Master Collection and still can't get past the "Mediacore Initializing" window. All the other CS6 apps are working fine and I don't have any plug-ins installed as of now.
Also, After Effects CS6 with Mountain Lion is working just fine on my MacBook Pro so I'm wondering if Mountain Lion is really the cause or not.
I've tried are throwing out the preference files, but that didn't do anything either. Furthermore, I still have CS5.5 on my computer and After Effects gets stuck in the same place with that version, as well.
If anyone has any ideas it would be much appreciated.