Can someone help with ambient lighting and a big skybox texture glitch?

Hey, Im still making my first map, just trying to get a bunch of mapping techniques down before starting on a real one. Although, as of now there are two major problems with my map; first off, it’s too dark. I added a light_environment and an env_sun, but neither helped. Is there some setting I have to change with either of them, or do they have to be in a certain place, or what? Also, I made a big box around my map with some sky texture, but for some reason it overlaps things I’m looking at. Like, for instance, in the map you start out in a completely sealed room, but it looks as if the wall only comes up to about your waist. However, the wall doesn’t act transparent or intangible; only the sky texture comes through, I can’t see anything else, like the tree or NPC I placed on the other side. Also, nothing can actually move through it. Also, it’s only brushes and displacements; I can see props and NPCs just fine. Any help would be appreciated.

http://www.interlopers.net/tutorials/1783 - First map
http://www.interlopers.net/tutorials/3964 - Light Environment
http://www.interlopers.net/tutorials/1798 - Skybox

Hope that helps.

actually it did, ty