Out of the box, I've only noticed 2 problems.
1. Surround Sound is not working on Audigy card.
To fix this you need to turn off "Syncronize with control panel" check in the Creative Mixer app. Then go to your Windows Sound setup and select correct setup in the speakers pulldown menu (5.1 for me). No need to reboot, even tho it asks you to...
Every time I get message "Server is full". Even on empty servers. Not sure if my firewall is causing the problem (I can play UT2004, etc. without any problem online). If anyone knows answer to #2 let me know