A really interesting one. Incredibly atmospheric and creepy.
I'm not too keen on the ijkl bit of the controls - mouse would have been better imo.
The map was also very flat. It was basically composed of sections you could walk on (which were all one level) and sections you couldn't (which varied in height). A bit more variance in the levels could also make it easier to tell where you have and haven't been before.
Overall really enjoyed it - though I don't think I played it enough to do it justice!