This is wildly impressive that you managed to make a first-person platform puzzler in just 48hrs, it looks good, has a great atmosphere, is just a nice time. The only things I'd say were that the movement and collisions could definitely use some work, very easy to get stuck on or in things, and many jumps you sorta have to trip up, I also think it would have been awesome to have music playing throughout the entire thing, some sort of nice quiet relaxed track, but, something to build on the already present atmosphere, perhaps even one for each mountain?
I quite liked how smooth the transitioning between peaks was, and the hint system designed as chalk or paint on the rocks looked great and worked pretty well, the only thing that wasn't terribly obvious was interacting with things, having some sort of pop up or other visual indicator when you are hovering something you can interact with would be nice.
All in all, I really enjoyed my time playing through it, even if at the end it is suggested that my player on finishing his mission was promptly crushed between the mountain peaks XD
Really fantastic work!