I found something strange, and i can't actually say if it's a glitch or an easter egg. I was clicking randomly on the main menu, and then a black screen appeared with the words "Level -1 completed." Like when you finish a level. Then i appeared in a square, empty room, with the sign which says the level number, but instead of a number, it had a "?" sign. In the wall it says, on a nearly transparent color, "ZOMGOWNED". Now that i come to think at it, it can't be a glitch. Is this a test room, or something? It's quite funny, even looks like a "sandbox" level.