So I think I encountered a bug?
First off I would just like to say this was interesting! Very nice little game here. Heard about your game from "Horror Games Community" on Twitter.
I got to the cave and the professor did his thing, I had the mask on and was able to leave the cave but then I couldn't do anything? Walked around the area and I could look at stuff, but I was unable to activate the helicopter? Not sure if I left the scene too quickly? Not sure what happened.