Have you inspected the contents (as steered-to by switch-view priority and stop-views available) to see whether perhaps the offending block(s) are some other sort of view that doesn't look like a schematic / cmos.sch view that might be expected to be worth MCing and have the infrastructure to do it?
For example a veriloga block is unlikely to have MC stats to chew on, so nothing to do (although you'd think this would be more of a warning / info burp than a hard error).