Since I have used it, Cakewalk has incorrectly labelled Middle C, which is universally known as  C4, as C5. This causes problems with keyswitching in instrument libraries. You have to make the keyswitch an octave higher than it should be for it to work, which sometimes causes it to run into the playable range of the instrument, causing unwanted sounds that you have to track down and correct (set velocity and volume so you can't hear them). And more to the point: is there a way to change this?