It's not only about the gunshots dude... think about the footsteps
If you make a room with a wooden floor... such as your library (currently it's not, but to me you *should* change this and make a wooden floor in the upper level of this library.) or if you walk on grass, dirt or whatever, you'll enjoy these sounds.
You can't really figure what it'll be if you're alone in the map testing it, walking around, stopping, pointing your gun somewhere and shooting at stuff. You need a bunch of players running and fragging happily together. You'll see you can even locate a player by his footsteps. It's a non neglectable asset for a tactical deathmatch game.
*edit*
saw your new pics
o_O
I'm out of words
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*edit 2*
@SoUlFaThEr: I've uploaded my materials.txt file for CS 1.6 (should work for CS 1.5 too) for you in the Filebase, look it up in the "Other Stuff" section...
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