For a first map, this is very good (my maps still kinda suck). But there is still work to be done.
Max1. I assume you still have the max file for the bsp. You might want to fix some of the materials on the map (like, some seem a bit out of place).
2. Add a bit more detail to the environment. It seems very boxy right now. A good place to start adding detail is in the tunnel that looks like it has a crystalline texture. Warp the faces in there to give it a more natural look (unless that's not what you are going for, totally up to you).
Textures There are a couple problems with the textures at this point.
1. Yes, they do seem flat. Try adding in some appropriate bump maps in those shaders since you are using the flashlight so much.
2. For the scale that you are using some of the textures at, they are incredibly low res. Especially the ground bitmaps, which clashes with the higher res temple(?) bitmaps (sorry if I mislabeled them, hopefully you know what I mean though).
3. Bordering textures that don't match. I noticed this on the temples(?) mostly. One side would be one texture, and the next side would be a different one. And that's fine, except that the textures were very different, so they looked strange next to each other. An example from the original campaign of what I mean is on TSC.
This isn't as big of a deal to some, but it bugs me to no end. Notice how there is no texture blend at the intersection (blue) between texture 1 (red) and texture 2 (green)? That abrupt change has always stuck out to me. Again, some people might not care too much, but it's always good to remove as many of these instances as possible.
Other thingsI noticed that the player gets attacked by the flood almost instantly. You can fix this in a few ways.
1. Move the spawn point to a place that isn't shared with flood spawns.
2. Using scripts, delay the initial flood respawn by 5-10 seconds.
There is probably more to be said, but these were just my first thoughts.
edited for formating
Edited by SAS on Oct 24, 2013 at 01:47 PM