As far as I remember, there are no flagrant errors, only "oh, I forgot 11:12 to 11:19 counted, whoops" sorts of feelings, which Professor Layton has everywhere!

I do seem to remember some issues with the letter recognition, but I also had problems whenever I tried to write the numbers 4 or 6 that it would recognize them as something else, so maybe my handwriting just doesn't translate well to a DS screen.