Thank you very much! I appreciate it. I'll check these out tonight. Still can't believe the involvement of a simulator from 2006 that wasn't commercial. Open source is the only way!
If you need some ideas about what to do with anim8or, I have also written a small tutorial on making a payload bay in anim8or.
http://www.orbiterwiki.org/wiki/Making_a_payload_bay_in_Anim8or
Also the tutorials on the Anim8or page should be a must.