I had issue like, it asked me to press "E" to take, but it didn't worked and the text disapeared. I had to walk around the cube few times to have the text again and to make the button work. It happened two times during the game.
And I thought the game freezed between the first and the second level, as we appear in the complete dark, but it's not an issue, and it's a bit cool because it's a bit scary to go in the dark :)