Too many glitches
The game is fab! The layout of the castle, the way Nearly Headless Nick shows you where you need to go, the characters, the individual levels and how it sticks to the books pretty well are all positives. It's not too hard but there are parts that will have you thinking aswell.
However, there are too many glitches in the game.
There are small glitches like arrows telling you that there are boxes or characters not there, medium glitches where the control directions are wrong and then the major glitches which mean you cannot complete the game.
The producers know of these problems and are "currently looking into them".
Due to the glitches I would leave buying this game until the major ones are fixed as it's very irrating to be 98.7% complete and not be able to finish the game (trust me, I know!!!).