Played it. Finished it. Overall, liked it a lot, but I've got some constructive comments:
-For the love of Christ, don't disable jumping and crouching. That's only going to piss players off, especially in a mod with a bunch of new monsters, 3D floors, etc. I use jumping quite a bit to do relatively mundane things like stay out of nukage, avoid Revenant fireballs, and other stuff. If your levels aren't intended for jumping, then put that in the readme, but don't outright disable it, that's bogus. (In fact, I'm amazed it's even possible.)
-The music is, overally, pretty great, although I obviously recognized some songs more than others, and some were better done than others. (Tallon Overworld is a great song and fit perfectly in the level.)
-Fuck whoever made the berserker runner screaming dudes, and fuck you for putting them in.
-The final two levels need SERIOUSLY toned down. Fuck the "Crackodemon," he's obscenely powerful and would sometimes kill me in one hit after using resurrect in the console. I played with vanilla weapons (with Stomper graphics) so I was routinely getting my ass handed to me by some of the boss monsters. (I only started using resurrect after it became clear that I was just getting killed in the same place over and over again, and I wanted to see the end.) The last level is just fucking insane and I'd love to see someone actually complete the fucking thing legit.
-You GOTTA take out the green Volcubi in the first big room of the last map. If he flies too high, and you shoot him with a rocket launcher, he can blast backwards into other parts of the level and has a hard time coming back. I had to enable fly and go chase him down to get the rest of the level to lower.
-The entrance to the secret level is a pile of bullshit. If the player falls into that nukage pit, they have no choice but to die, and I didn't find any radsuits in the time I played the level, so I finally gave up and God moded so I could explore, and inadvertently found the secret exit. Not the coolest way to find it. I would consider doing it differently, or putting a radsuit nearby when you fall into the pit.
Other than that, I'd say it's pretty good. The texture set is fantastic and the usage is stellar, and most cases of architecture are great looking and play well (although I'm not a fan of those spiral staircases, they're easy to fall off of.) My main issue is that I always seemed like I was walking around with 100% health (or close to it) and then I would run into a room literally filled with bad guys who would take me down to 25% or less in a matter of seconds. I don't really like my encounters to go that way; I'd rather run around with 40% health and worry about just a few monsters being able to kill me, it's much more tense that way.
Now just for some technical comments:

MAP01: Some of the pillars are too close to the walls in this room and can't be walked around; this makes it hard for the player to maneuver. (Also, some of the lights scroll, and some of them don't. I don't know why the inconsistency.)

MAP01: HOM texture.

MAP02: This texture goes into the floor, pretty sure it shouldn't do that.

MAP02 (I think): HOM texture.

This elevator worked weird. The switch lowers it, but it seems like walking over the linedef to step off onto the lowered platform made it go back up. Kind of counter intuitive.

HOM again.

IMO this could do with more of a "ledge" overlooking into the red room. I guess it's fine as is, but it looks like the wall is just paper thin.

Enter the room with the yellow key. Have to exit with a switch, forcing me to fight that Cacos, rather than pick my battles and get the fuck out. Total bullshit. Don't trap the player by changing the rules. If a door required a simple key to walk through the first time, it should exit the same way.

Blue armour in a room with a Hell Knight and some weaklings. The reason I bring this up is it's on a little bit of an extended "ledge," but you're fighting a Hell Knight in very close quarters. The player's inclination is to get with his back against the wall and circlestrafe, but this "ledge" sticks out like a sore thumb and blocks the player, forcing him to move forward and then continue trying to move right. They won't be expecting that and it can get them killed. Either inset the "ledge" into the wall, or if you're dead set on it, make the edges of it angular and smooth them out a little to make it so the player can "glide" smoothly over it instead of getting stuck on the architecture.

Texture is poking through the wall or something--slime trail?

I tried for a minute straight and COULD NOT FUCKING hit the switch and get onto the platform fast enough. Make the platform stay down longer. There's NO reason for this bullshit.

Like the yellow key door in the Caco room above, there is NO reason the entrance room in the last level should permanently close behind the player. I left some weapons in there, expecting to be able to go back and restock mid-fight, only to have it close behind me and screw me over. Don't do that.

The sky texture loops oddly and doesn't look right.
Overall, still a fun romp, just has some issues that can be worked on. I didn't try out Survival mode because it doesn't interest me, sorry.