Great job on this game guys!
I really enjoyed the atmosphere, tense and creepy, and the concept was intriguing with lots of possibilities.
Now that I look at the images I think I might have missed some part, though it was a very pleasent experience :D Not to mention the fact that you made it for charity.
I made a video about it :
if you want to check, in the end I tried to speculate on the meaning of the game, let me know if I came at least close to it, best of luck for the full release!