If you're talking about pink reflections in the windows and stuff, make sure you have some env_cubemaps and then run the buildcubemaps command. Then when that's done, reload your map with the 'map' console command. If you get an error, use mat_specular 0 before you use buildcubemaps. You can reset mat_specular to 1 after you're done. You may also need to set sv_cheats to 1.
You have some pretty nice areas, but if you're going to have large walls with one texture on it, try not to use one that repeats it's pattern so noticeably, or increase the scale of the texture. Remember also to use a different texture on your ceilings than the ones you use on your walls. I think it just looks nicer that way.