Trial version I hear, so I won't be too harsh! :)
I liked how you embedded the controls in the world and introduced the key+door mechanic by making the player search their starting area before being able to proceed. Though, for picking up the keys, I would've liked to have used the semi-default "interact" key of these sort of games, E, rather than left clicking. Or even an auto-pickup.
Beyond that, the environment was nice, but the collision on some of the walls seemed a bit harsh. I felt like I'd get stuck when I shouldn't sometimes if I got too close to walls. And as another commenter suggested, adding some sort of puzzles would add a lot to the game and make the sections feel more unique!