I finally gathered all the Death in Venice original music files and sent it to TMOA. You can listen to it here as well (find the widget on the right side). :)
It is really fun to compose the music for the movie that you are helping to direct. We deliberately extended a few seconds here and there when we felt an extra little musical phrase would help. And of course there were long discussions on whether music is necessary at all in certain places.
There are a few recognizable recurring themes used throughout. One of them is a short motif from Verdi's La Forza overture which I found to be handy - this overture is the music you hear at the opening intro with the mask and that church on the other side of the Piazza San Marco - what's the name of that? There is also a 'revenge' theme, associated with Sebastian, and a 'love' theme - prominently played near the end of the movie.