I really enjoyed this game - up to the point where a bug stopped me from proceeding. I've got the yellow key, and the only place left I can seem to go is through a yellow lock, but it won't open. It's the one right at the beginning of the forest coming from the starting area. Really frustrating that I can't finish this game after getting so far into it - I've tried exiting the screen and returning a few times, but I'm just treated like I don't have the requisite key.