i'm not sure you would want to!!! i never had poser4 but i still kept my poser5 when i got poser6 but anything i made in poser5 wouldn't load into poser6 without a lot of hassle!!! in poser 5 when i saved a character it averaged at about 100Mb in poser 6 if i make the same character it saves at about 3Mb!!! i've stuck with poser6 since and eventually deleted my poser5!!! because everything in 6 in so much better!!!!! sorry not any help to your question!!!!!