I regret to tell it but this map is practically worthless. It consists of four cylinders of decreasing diameter put together like a funnel, with the inevitable lava trap at the bottom. No architecture whatsoever, no details, no theme or unique atmosphere. Lighting is bland and uniform, with no visible light sources. Only the Rail Gun is present, with very little ammo that is quite hard to get. Strategy? Forget it! Game play consists of frantically running around the circles and taking potshots at your you opponent(s). The place is literally stuffed with health packs (67) and armor shards (44), these are everywhere - it is difficult NOT to pick them up.
It is hard to give constructive advice to the author. I suggest that he should study the maps of others and read a couple of tutorials on level design before attempting to make another map.
On a scale of 1 to 10 I rate this map 0.5 - not zero because it can be compiled and run. Download it at your own risk, I wouldn't.
Reviewed by speaker
Tig's notes: One thing about this map that may interest other Authors is the method used to create the background environment. It is a similar method to how Unreal does it.