Its a pretty interresting map.
The industrial-desert theme is quite original.
The texturing is nice, even tough it could use some more contrast. This has a very similar texture set as academy, but unlike academy and frozen, it isn't ice/freeze-themed. Maybe you should mark the theme a little more, by creating sand heaps or something like that.
The geometry is nothing to complain about, it's just like it should be.
The lightning is fine, but I think it could also use some more contrast. There are plenty of shadows and areas wich are fully lighted, but it somehow isn't giving there really is some difference. Maybe you should put the ambient a little lower or the skylight a little higher?
The atmosphere should actually feel like the skybox is telling you, a sun wich really burns on your head.
The detail is ok, some nice solutions for trimming edges has been used.
The clipping/noclipping isn't bad, but just like other's already commented, be sure that a player understands the what's "outside" of the map.
The flow is nice, but that's just because the map is so damn open. From this aspect the map is actually nothing more than some (short) stairs wich are leading you up and down.
The gameplay isn't that great. Efficiency will end up into "rifle combat" and for insta, the ammount of playerstart is just too low for that mode. When you stay on certain higher platforms, your able to see about 7 of the 9 playerstarts. This probably ends up into camping till you drop.
Anyways,
Nice map, you can see there has been spend pretty much time in it.
I would recommend to observate metl3 and compare this map with it, especially from the aspects lightning, texturing and detailing, since somehow metl3 has that "burning" atmoshpere wich this map just doesn't has.
8/10 for now!