I've just upgraded to 2012 SP1 and have noticed a recurring problem with the Rigid/Flexible properties in an assembly.  The file was created in SW2011 and then re-saved in 2012.  When accessing the configuration in the assembly which has the flexible option highlighted, the assembly and all its parts disappear from view.  They show in the feature tree as neither hidden or surpressed. In addition however, the configuration itself appears as suppressed (grayed out) but is not?!?  I can delete the configuration and set it up again repeating the flexible properties but I have several assemblies with a configuration of this nature and obvioulsly don't want to have to do this everytime.

Has anyone experienced this or am I just dealing with some corrupted files?

Cheers, Carl.