Nice, simple little map. Game play is much improved over most of your previous work. The weapon/ammo ratio was just a hair short, maybe another box of shotgun shells and a couple more pistol clips would do the trick. Also move the first sixpak a little deeper into the map, as it really wasn't needed so early on.
A few things needed to be polished, some mis-aligned sprites, some stronger shading in the corridors and a few other areas, and maybe just a bit more detailing or structure work in a few areas as the map seemed a bit too plain in a couple of spots compared to the rest of the map. Other than that, pretty good.