Questions
If there are questions about how to use a certain feature of D2X-XL, consult the links provided in the readme file, or visit my Descent site and read the manual pages.
CTF
Standard Descent 2 CTF is no full blown CTF. It has several severe flaws. If you want to play 'real' CTF, have the game host select 'enhanced CTF' in the multiplayer options menu, and make sure to use an enhanced CTF enabled map. My map 'With Flying Colors' is one, and I believe it might play really great in CTF mode. Give it a shot.
Networking
Networking problems might be related to the nature of UDP/IP communication, where lost data packets are not accounted for, and there is no way to detect this and retransmit them. During some stages of joining a game, this is critical. In-game, this usually isn't, as state updates occur frequently enough.
Btw, if you set pps to 10, you will inevitably have an update lag of 100 ms, even if your 'ping' is better.
If all participants use high bandwidth connections, try to increase pps. You can also omit shortpackets, that will give you better positional info (less jittering of other players' ships).
I'd also like to know whether networking problems increase with growing number of players.
Tracker
All trackers seem to be down. I'll ask KoolBear from the Descent BB about his.