Well, I'm having this problem form a while ago, I think it come from Poser 6 and it's puzzling me...
The Vespa has a couple of dials in the "Body" that changes the rack and the seat with a rack with a sparewheel and a second seat for a passenger. In the CR2 file using those dials the original OBJ is changed with an alternate OBJ , I checked what I'm able to check: position of files, files not corrupted etc. and all is ok, but those dials refuse to work. Yep, I reinstalled all from scratch but still not working... I partially solved the problem importing the alternate geometries as OBJs but still, I'm sorry that the beloved Vespa has this problem ... Any hints ?