I have a shaft assembly that is turned in a higher level assembly.   I would like the turning profiles to be part of the design library so they can be used again.  When I add the a design feature to the assembly though I get the error "You may only select references from the part being edited.  Please reselect".  Is there a way around this or do I have to be in a part to add a design library feature?   Should I be using some other type of element to do this?

Thanks