AWESOME PIECE !!! I don't have much time to make a full critic,  plus i don't seem to be able to find something that i don't like...    (maybe the part near the end... i think that it could be improved...it'snot bad, it just could be better). 
and the piano part... hmm, if i can guess right... 
re, fa, la, mi, fa     then (one semitone down after four times) 
and the first melody...   
re, mi, fa, sol, la, sol          - sol#, re, do# 
or something... dunno,  never tried playing it, and my pitch isnot the best in the world :P