Nice! Can't download as of now, but I'll give you some advice based on the screenshots.
Screeny 1: Entity placement is good, but I see seams in the floors. It would look a TON better if the texture was seamless. You can do this with quite a few image editors. Also, why is the ceiling a floor texture?
Screeny 2: Looks good, but again, the ceiling looks out of place.
Screeny 3 and 4: Very nice, looks very realistic.
Screeny 5: Looks a tad bland, but otherwise, not too bad.
Aside from a few tidbits of level design , it looks like a fun play. Nice job!
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