Hello, i'am modelling a plinth foundation as a nested family (lean concrete, slab, pedestall,..). When i try to modell the waterproofing on a slab i use "split surface" and "paint" and everything works. When i load the (sub)family into the host family the splitted surface (and consequently the painting) disappears. Then i edit the family and in it is ok. Look at the attachment to understand better the problem. Please help me