Hey, I saw you asking about how to use blender and unfold pep files (That wasn't exactly the place to ask, btw).
Weeell, I have no clue how to use blender. Tried it, and got nowhere with it. Instead of blender, I would recommend using Google Sketchup. It's not anywhere near as fancy as Blender, but it's a lot simpler to use, and get's the job done. It's free, self-explanitory, and google has a searchable database of 3d models for it that can be uploaded straight to the program. The lastest version can be downloaded at
http://sketchup.google.com/intl/en/download/index.html
Also, you can't use a 3d modeling program for unfolding. You must use Pepakura designer (not viewer, DESIGNER). see post below (message was too long to send in one peice) for more info.