We've just upgraded to MR2 (FM, AS, QS, RS, MS, ES) and have found a problem.
Our cube models contain calculated categories in the time dimension. E.g. Prior Month Variance which is current month less prior month. The MR2 version of Analysis Studio shows this calculation as "Time1" with the same stucture as "Time". We cannot open this level to see the members. Even in Report Studio if we try to open the level to see the contents we get an "Unexpected Metadata Error".
The work-around is to put these calculated categories into a folder and then they work as before.
Have fun! :)
Bluey