The main problem for playability for me was that I couldn't go full screen (in web), so my cursor would leave the game and the camera would become unresponsive! :D Otherwise, that was a very blank room!

First off, I had some technical issues. The web version will show the credits all right, but when I click "Start", the browser freezes completely for about 10 seconds or so before there is a crackling sound, the music starts to play and a popup says "lost webgl context, please reload". When I do, all repeats again, and if I don't there is nothing rendered so I can't play.

Tried the Linux version and it works fine apart from some hickup after pressing "Start". So it seems you have some demanding work going on right after the scene loads.

The music fits nicely and other than the above the game works fine. Regarding the gameplay I'm a bit torn. On the one hand, most of the time there is no sense of direction, even using the controller to show the obstacles usually doesn't help much as you can't see the room's boundary or any fixed point. I was running around randomly, collecting the batteries, using them up (to mostly no avail) and eventually be pure luck finding the exit. On the other hand, maybe that's just the point of the game, to feel and be lost. However, due to the lack of any means of orientation as a player I didn't feel any accomplishment when finding the exit.

Using the controller should, in my opinion, allow the player to actually gain information. It's perfectly fine to have the player run around and make guesses about the environment, but then the usage of the controller should have a "alright, now I know more than before!" moment which wasn't the case for me. Also the problem with running around and guessing in the current state is that you don't know if you are actually running or have your face right against a wall. This could be fixed by, for example, having foot step sounds if you actually move, or by making the player leave some kind of probably vanishing but visible trail.

Another option would be to abandon the third dimension (as in 3D) as it is not included in any game mechanic (apart from being able to look up or down, but there's nothing ever to be seen. Instead, make a 2D game with a top down view where the level is fixed and the player moves around on the screen. This way as a player you'd at least know where you are, but not where to go in a maze with invisible walls. You could add some moving walls or another kind of dynamic obstacle to prevent the player from  just walking along the walls until the exit is found.