right create a new folder on your hard drive called:
server.ut2003
unzip the dedicated server zip file into there.
this is now your dedicated server
get your cdkey form the above link, unzip that file and double click on it, click yes to add the contents to the registry (im pretty sure its a .reg file)
unzip the bonus packs and install them as you would normally do for your own retial copy of the game, only point the install screen to c:\server.ut2003 or wherever you created your new folder.
to create a server go into the server.ut2003/system folder and make a copy of the UT2003.ini file. rename this copy server_ctf.ini
now u can edit this ini SPECIFICALLY for ctf.
go thru all the settings, and adjust them how u want them, timelimit etc.
check your port number, do you want to keep the default 7777 for example?
stick an admin username and password in where their needed.
save it.
your .bat files are what start the server. I've uploaded a ctf bat file for you here:
http://ftp.wireplay.co.uk/ut2003/utils/server1_ctf.zip
unzip this file into the server.ut2003 folder, NOT inside the system folder but in the root of the server.ut2003 folder.
if you right click on the bat file and select 'edit' you can view the settings of the server and change any u want.
double click on this bat file and the dedicated server will start, and you will get a dos window showing you the log of whats going on.