Concerning the enclosing sections (ie the first and last 'bits'), try singing the melody. Play it at a tempo where you can breath one breath throughout the entire phrase, and don't be afraid to use almost-excessive rubato (note: ALMOST-excessive).
If you run into difficulties with the middle section remember to play the left hand lightly, and think of a scherzo. In the chromatic scales try practising by using dotted rhythms, and then invert your dotted rhythms, it helps tremendously.
I have already performed this piece, and I am preparing it for conservatory auditions now... This is all advice that I got from my teacher today.... It works wonders..... Cheers
