Hello,
Have you find the solution to the stopped-server issue (clr.dll, ntdll.dll , .NET 4)?
I have exactly the same problem on FIM Sync 2010 R2 sp1, it seems better with gcConcurrent to false,
but when I stop running synchros during 10 minutes and re-run a full sync, FIM throws the exception at the first execution profile.
Thanks for your help