I'm still learning. I don't know much about the material room or the physics room or even the fitting room. Despite having used Poser since version 2, there are just some things I'm not mentally equipped to grasp as swiftly as other aspects of the program.  That said, I really hunkered down to learn the program with version 4 (up until then, I'd just been swapping textures and hitting render). Once Poser4 Pro Pack came out, it was a done deal for me. Took me less than a year to figure things out enough that I could get my own stuff rigged (much thanks to Phil C for guiding me along).