-Mouse smoothing is terrible. If you have to have it in the game, at least make it disabled by default.
-Add the option to disable post-processing.
-Make RMB go back in menus.
-Torch particles are in local space instead of world space.
-Add free look when climbing chains and make A and D rotate you around them, because you can barely see where you're jumping like this.
-Dialogue text box doesn't scroll to fit the last line entirely.
-I could see someone getting stuck on the puzzle where you have to use the water gun to lift a barrel under a lever. You should make it clear earlier that they're physics-based. For example, you could have a lever that you need to pull down that's blocked by a moveable object below it.
-Why do weapons disintegrate after killing two enemies?
-Enemies with bows backstep off edges to their death.