DM-Alice

This deathmatch map is set in a large outdoor arena with a number of platforms and unstable gravity in certain areas.

http://www.gamespot.com/pc/action/ut2004/download.html?sid=6167731

Looks like a fun map, could be interesting for invasion. It looks like it might lag a bit though, maybe?

In addition to asking for a physical address for registration, GameSpot also requires you to install a "download manager." It sounds fishy to me, so if you can provide a different way to access the file, then I will look at the map.

Here you go, Shan.

Verification:
The author's post on it references a contest at AddonDB with the official download page.

Thanks Moof!