We have encountered several disturbing Pro Tools errors beginning with "Assertion in..." and referring to a volume called "Development" which does not exist. They occur when bouncing or saving sessions sometimes. There is no known fix. More info can be found here:
DUC forum Asssertion error Page
If your session will not bounce because of one of these errors, the workaround is to bus all your tracks to a stereo audio track, record them onto it in realtime, then use the "export regions to files" command from the little drop-down menu above the regions list on the right hand side of the edit window (sometimes hidden). Described here.
Enjoy your new stable and wonderfully reliable software! Kindest regards, the Digidesign Amateur Tools development team. I mean Pro Tools...