I did the 4 puzzles and I gotta admit I find it actually pretty challenging. I love the way you gotta solve the puzzles, as is not as hard as hell, but it's not easy like some other logic games I play. I love it.
I just dont know what the hell happened, cause when I finished the last puzzle, I went to the stair to climb up and what the hell, the game tilted D=. Anyways, despise that bug, the game is excelent.