i had 6.0 default running just fine on osx. in 64bit everything running, bfd2, play ewql, battery, omnisphere, predator, kontakt…
did the update, only omnisphere and kontakt4 now… oh maaaaaan…
no hope with bfd, but with other instruments the problem is only with new tracks/instruments. they all there and working when i open project that had them on already.
Based on the limited information above, and not knowing what you did, I for one can’t even guess why your problems are occurring, but obviously what you are reporting is abnormal, and I can’t see why the update would have caused that on its own. Perhaps do use Time Machine to return to 6.0, then before, you try the update again, have a close look at your system and do a bit more troubleshooting of everything before you try updating again. Hope you find the cause as I’m sure it’s upsetting and time consuming trying to find the reason. I can assure you that the update has gone smoothly for many users who have similar Mac systems.