As was pointed out the map is very cramped, navigating it thus requires mandatory skill. My limited level of skill may well be getting in the way here, but I kept getting snagged and stuck. The low ceilings, IMO, would have been nicer if they had been 50-100% higher. The gameflow did not feel natural, I never felt like getting anywhere, more like repeatedly arriving somewhere. Again, my biased opinion.
I would have loved a version of the map, with nicer lighting, less cramped, more generous layout, and more connected paths.
Despite that, your sense of lighting and color are great, it shows in this map. I may not keep it on my harddrive forever, but for now it's enjoyable and that's what really matters.