To answer both of your questions.
1. TW2002/TWGS is an all in one package. It is a new version of TW2002 made to run in windows. The TWGS portion of it. It just a sysop interface for TW2002. And to make it easier for BBS software to connect to TW2002. It also makes it so that there is no need for a BBS to run TW2002. Synchronet BBS was a DOS based BBS software. It is currently a Windows based BBS software. If you are using the DOS based version. Then what you need it the TW2002 Doors version. This is currently at v3.09 . And this is the last version of the TW2002 doors version. You can get it here
http://www.eisonline.com/tradewars/Download.html
If you are using the windows based version of Synchronet BBS. Then it is best that you use the TW2002/TWGS version. Although you can still use the door version. You might have problems running it in a windows enviroment. You really only need the TWGS Lite, 4 node, version. Unless you beleave that you will have more people than that. Playing the game at one time.
2. The registration information for the door version. Will be included inside the distrabution file. Or just contact JP by email and he'll get back to you as soon as he can. He is very busy with working with another software company on their new game.