1. Colourwise, they are the same. But Goat is a lot tougher than lambskin. People often worry about scratching their lambskin on branches, but those with Goatskin wear their jacket worry-free(for the most part).
2. Wested recommends cotton body, satin sleeves. IMO, all satin would be too hot. With cotton sleeves, you may have to worry about snagging the jacket sleeve on your sweater.
3. I can't remember which is accurate, but D-rings slip on lamb(and the Indy cotton, apparently) because of the light material. Some people don't have problems, but that's because they leave it alone. If you keep adjusting it based on how tight you want the jacket to feel(thick sweater, looser faster) then it will defineately be slipping.
4. Peter stated here in the forum that two different versions were made. One with no gussests and a stunt jacket with double gussets which were used for the fight scenes. Flathead seems to have a lot of knowledge on leather jackets, so I'll let him answer that
http://www.indygear.com/forum/viewtopic ... b394998c83
Enjoy your stay at COW and remember to check your wallet at the door.