Sudden fit of creativity, last night, has resulted in the underwater section of the tower being mostly completed. Having Tali around to throw out ideas, rig up some fancy particle effects, and haul me up when I was going wrong helped a lot. Having Tali around in general is pretty much fun, actually.
Down the far end of the corridor, there's another airlock, and the open door to the main living area.
Anyway. I'm pretty happy with how this is going. It still needs some sound effects, I think; clangs as doors open and close, and vague creaking and dripping sounds. And there are ... things ... that have yet to be installed, outside. But, overall, I'm fairly pleased.