Finally got to play it yesterday and took me about 30-35 minutes, but then I spent a lot of time just looking at stuff around, as the design looks amazing!
It does feel completely different than the first one indeed, despite both having very strong The Abyss vibe of course - and I think I liked this one a bit more, due to it resembling my favourite part of the level. TROR was implemented flawlessly once again, it gave the level very strong 3D feeling and was much more pronounced than in the first map, but didn't have any "gimmicky" thing to it - great job!
And the play on shadows was fantastic, really liked it. The puzzles were also fun - especially the 2 level rotating thing, but also the shrinker puzzle was something I liked.
Few minor complaints:
- agree with Mister Sinister and Merlijn on the random alien sounds, they seem to be overused around in this map (especially some being in sectors right next to each other it seems),
- the final battle seemed a bit too dark for me, it was hardly to see what's shooting at me and playing without auto-aim, it was tricky to hit things. Also not sure about mixing slimers and protector drones at the end, as all the protector drones ended up being eaten by slimers
- the wall textures around the room with the raising stairs moved along with the stairs - I think it would look better if their orientation was changed with "O", so they would just stay in place (also it resulted in the textures being a bit misaligned at one position of the stairs),
- this one's not on you but on TROR I guess, but some random sectors seemed to drain health/boots energy despite not having the acid textures, for example the highest step in that hole you had to enter to reach the top floor above the acid early in the map.
Overall, great experience, congratulations again on the release! Found 5/8 secrets during normal play, then backtracked to look for the others - the very first secret in the map took me the longest to figure out. Also it seemed some monsters respawned on the way and got stuck into not following me through these long stairs, not sure if it was intended.