Mostly an FYI for others.  I found that an assembly with a circular pattern of a subassembly failed when asking for a section that does not cut through any portion of the master subassembly of the pattern.  Error message was would create invalid bodies.  Will section fine on planes that cut through the master subassembly of the pattern.  Replacing the pattern with actual copies of the subassembly instead of using component pattern everything works fine.

greg