Thought it was interesting at first but as I played it got boring fast. The mechanic of throwing pebbles, while neat initially, is ultimately a tedium. I was rapidly tapping Q just to light my way and my finger got tired of it, and it basically just turns into an annoying-to-use flashlight. If they had a limit, or if they stayed lit up, they would be much more interesting to the game IMO.
I turned off a machine under where I spawned but I didn't recognize that it did anything at all, but I think a sound stopped. I ultimately stopped a little bit after that because I died a few times. Are you sure the game needs death? It seems a little bit more like a narrative adventure game, not a challenging platformer game. Consider what the game would be like without players being able to die and having to start over.