Maybe I shouldn't be doing a review of this mod since I did have a part in it, but I just won't comment on the voice acting. I have to say, I was quite impressed with the production of this SP level. It was done really well ... not just the mapping, but the animations and the sequencing and stuff. This is not one of those levels where you just fight a bunch of spawned NPC's. This was quite well thought out. In fact, the whole level is mostly puzzles. I'm horrible at these things. So I did use the walkthrough that was provided (it'll probably be posted by the author later in the comments) and even then I had a bit of trouble with the second puzzle.
If you enjoy a good continuing story, a pretty map, challenging puzzles and great production, download this now. I've heard nothing but great things about this mod. And I actually played through the whole level and was quite satisfied with the end. Great work guys!