I discovered a serious problem for me with my 2006 assemblies when migrating to 2007. Contacted my support and swx are looking into it for sp2., probably another 1/2 months. The problem is concerning subassembly orientation , distance mates are realigned in the other sub assembly configs causing the orientation of parts and subassemblies to change without mate change. its a huge problem for me because i rely on assembly and configuration management for my work. I have reverted back to 2006 until this is fixed. Any one encountered the same problem? Cheers Mo.