Just about everything out there is designed to work with Poser 4. Sometimes you'll see some items that say they're designed for Poser 5 only. But that is a small percentage. Remember, Poser Artist is really Poser 4 in a different box. The biggest pain is the need to convert the jpg bump maps to BUM format. That will take lots of time, and you may have to hunt for the files to convert. Sometimes they'll be labelled "texturebump.jpg," and sometimes cryptic names such as "textureb.jpg."