Warning: No bot file has been included and the level will require the start up command line option +set com_hunkmegs 128 to load without a crash. Even with this command line option people have reported issues. Others have had success with the ioquake3 engine.
toxic_fabric by Devils Right Hand is a difficult to review map. The level of enthusiasm and excitement for level building is bleeding through the brush work and construction that you really do not want to say anything bad to dishearten the author. On the other hand, as a reviewer there is no choice but to be honest.
This map is adventurous and feels a lot like an expanded version for the Unreal classic, Deck 16. Surrounding structures and areas flesh out the environment and you are now able to travel throughout the full industrial complex - including outside.
This is all great, but lack of experience on the author starts to show.
Much of the machinery and details do not consider or factor in the player size. Placing a player model in the editor and using the console command cg_thirdPerson 1 is a tip for the author for future releases.
As a custom level author, it is your job to make the release as playable as possible. You do not have a development team behind you giving you weekly feedback about what the game engine needs to work correctly. Letting you know the technical ins and outs. You need to do that research yourself. You are the one that needs to be very self critical and self reliant.
As far as game play goes, the release feels more like it belongs in a Half-Life single player mission. The full layout does not suit Tourney, DM, Team DM or CTF games at all. For example, there is a single door to the outside, yet you can run all around the map. The map is huge and can take a long time to traverse due to very limited use of teleports and lack of connectivity required for a good Q3A release.
Many of the map features are not clipped as well, this means you can become snagged or stuck even while running around.
Highly suggest the author learn more about the technical side of mapping. The console is your friend and commands like r_showTris, cg_thirdPerson, r_speeds will help to get you started. Research is just as important as a idea.
Skip this map but keep track of what this author does next.