Well i took a look and it seems nice so far, those blasted round corners have more or less a pillar making them rather a circle, making it not that easy for humans to wait in a corner, shoot with incredible accuracy, run away, repeat.
And his idea about having some sparkers move around are interesting indeed, shouldnt be too difficult to do in DECORATE, though i'm no expert myself. Would contribute to the theme, in any case. Though aside the Hell Froze Over map i havent seen much hellish themes in GVH.
So far looks nice, but hard to say more about it yet, havent seen it in action really. Also, i am capable of hosting, but hey, i'm bound to lag somewhat, in particular if its more then 4 players or so. :P
EDIT: Cutman, did you notice the map version i uploaded that has no camera yet? I think that one should do, and probaly saves you some editing. Now its just steam and fire, neither lag and steam only makes noise.
I'll copy the link here in any case. Didnt check if it still works though;
http://www.speedyshare.com/files/22900177/GVHLMv3.zip