I'd updated various parts of the level. Here is a general breakdown:

Added ladders to the map. They should all work with minimal fuss.

Replaced any lingering older texture with a newer texture, so they should all be sharp. The only exception is a static screen near the radioactive reconstruction area. This monitor is part of an incomplete revamp of the screens.

Added some more lighting tricks to simulate a light that is powering on to better simulate how System Shock lights work.

Added some generic level garnish. A lot of the generic stuff in the game have not yet been built, and cannot be added here, and some of the stuff need to be rebuilt, but for now, there should be a handful of things to help clutter the map.

Moved the music to be controlled with the Music slider bar in options. Now, if you don't like the music, just turn it down in the options menu.

Added Elevator music that plays only when you enter the elevator. I have no idea how this is going to work with multiple people on the map, so good luck! My DOS computer is not currently set up for recording, but I will add the radioactive music when I can.

Corrected some texture issues with geometry.

This update is an attempt to make the map less annoying for GMod players in preparation for next major update.

Some more adjustments for Garrysmod specific limits.

Updated doors, lights, and a ton of other stuff.

Initial addon creation.