UT2004 File Extensions and where they go:
 
 .ukx  -  goes into Animations
 .ifr     - goes into ForceFeedback
 .ka      - goes into KarmaData
 .ut2     - goes into Maps
 .ogg     - goes into Music
 .uvx     - goes into Saves
 .uax     - goes into Sounds
 .xml     - goes into Speech
 .usx     - goes into StaticMeshes
  .u       - goes into System
 .ucl      - goes into System
 .ini       - goes into System
 .int       - goes into System
 .upl       - goes into System
 .utx       - goes into Textures

 .ut4mod - Double click it, it's a self extracting/installing file. 
Anything with a .ut4mod you need to double click on and follow the instructions that it gives you. It basically installs itself. 
 
 If you are planing on running your own server
 Here are the default ports you will need to forward:

UT 2004 Server Ports: 7777-7779 TCP and UDP
 
 For the master server:  27902 TCP and UDP
 
 This readme file was provided by NoClanFrank ( http://www.levels4you.com/ ) and not the author of this mod/level/file. ;)