WF5: If there is a feature in the group, it can't freeze it, so PTC takes it off the list - I just tried an assembly and picked multiple components; Freeze was on the list (but grayed out for no reason that makes sense.) It remains on the list unless a non-component item IS on the list, where it is grayed out, no matter what selections are made. Sigh.
Another general enhancement - create dialogs that are a superset of all the options, rather than excluding all but the common subset, which is too easily the Empty set. If I can't Freeze a datum axis, FINE, but don't make the process of selecting 2, 20 , or 20,000 items a waste because one doesn't fit and the result is the Empty set and then not say why that is. The program logic is already there, it takes the item off the menu.