I liked the environmet. Took me 3 trials to finish the game, haha. Btw, I figured that while playing if you go fullscreen (if you're not already) the game gives a black screen. Overall, nive game!
I'll answer you again. I'm having a similar problem to your description, where when switching to full screen the screen becomes dark gray. In order to see the game, you just needed to click on the screen with the mouse.