A short tutorial on media can be found at:

I don't know if it will help but it can't hurt.

I'm not sure about the official release of v3.1 for linux but
there has been an unofficial release or two. There was an
announcement on povray.general about it sometime shortly after
the official windows release came out. I believe the posters
name was Glen Berry and had the url. Twist's site might also
have a copy of it laying around. For that try:

Ken Tyler