the GOG release is nothing special other than you get a working Red Baron(1) and it's amazing manual
I had no problem with RB3D in WinXP when merely copied my RedBaron3D Folder over from my Win98SE machine.
You need, minimumly, the XP sound fix program
For Glide emulation, I recommend dgVoodoo 1.50 beta
Once you have Red Baron 3D working with the sound fix and Glide emulation, but otherwise without
UOPs or other mods make a copy or 3 of your RedBaron3d folder
http://flybert.net/howto.htmlin one copy, I recommend WFP 2 as the best SinglePlay experience
HASP is very good too. It will only have the stock number of planes, but is entirely custom SWWISA planes and custom paints schemes
Both HASP and WFP2 fix minor bugs in RB3D SP
Make a seperate copy of RB3D for MultiPlay .. get the SWWISA plane set and other alternative plane sets for MP here
http://flybert.net/mpaltsets.htm