It's a nice game. However, there is one thing I didn't like. On level 2-2 there are some rooms looking like an old 3D movie without 3D glasses. They're hard to look at.
Also, I have found two little bugs:
1. On level 2-2 again, I've found a medium-sized room with an empty space in the top right corner that is separated with a thin bush-line (looking the same as those which player can go through). However, when player walks near it, the character gets teleported a few steps backwards or to a parallel corridor under the place. Did not affect my gameplay anyway.
2. When the player switches any weapon in weapon hotbar using inventory, all weapons reload immediately. This might be considered as a feature but I'm not sure.