Noel!! omg!! there is a whole host of issues!! I mean...god it would take to long to discribe but I think I can give you a pretty good discription if you go to this link

http://www.silverblades-suitcase.com/tutorials/htm/18.html

This was meant as a tutorial on how to optimize poser files for Vue but I think if you read through it...you'll get a pretty good idea of what most of the issues are, probably better then having me describe them all for you here.