You can still see through the sky even if you're not on the wall, so some kind of blocker needs to be put up. Another option would be to move the sky further out and make the outside wall of that room visible.
The way it currently is:
________
|#######
|#######
|#######
|#######
(where # is sky).
Potential solution:
________
| /
| /##
| /####
|/######
Then just fill the void with some ground or something and put a clip texture there.
As Pimp pointed out, there are a lot of dark spots (particularly in that room that's visible through the sky on the blue side), so you should probably add more lights. Perhaps scale the lighting up on the map as a whole, too. You can do this with a custom batch file by adding -scale 1.5 (or whatever number looks good) to the arghrad line. From previous discussions with you, I'm pretty sure your monitor is a lot brighter than most people's, so keep this in mind with your lighting.
A few nitpicks:
You should rotate the grain on the ladders to be horizontal. Also, where ladders go through a ceiling, you should only make the area that clears the opening have the ladder flag. For example, you can climb up the rightmost side of a ladder, hit your head on the ceiling, and have to jump down and try again. The easiest way to do that is to use a clip brush with the ladder flag and don't put the ladder flag on the ladder brushes directly. I know it sounds trivial, but things like that can be really frustrating in the heat of battle. Also, the bots get stuck on the ladders.
You should use a woodgrain texture on the edges of the tudor textures. Sometimes the wood of the tudor is there and it looks good. Sometimes not. Also, at least one texture needs to be aligned, but I can't remember where it was.
You have the phong shading on the purple barrels, which looks good, but it's not on the blue barrels inside the room discussed at the beginning of this post (maybe elsewhere, too -- didn't look thoroughly).
I think the metal plate textures need to go, especially on that Y support thing. They look out of place.
Anyway, it looks good so far. I can put it up for testing, but I don't think I'll be around tonight. I'll just give you a login or something.
