Raggedy, you're right that the score for Illuminata is quasi-classical. It was written by William Bolcom, a Pulitzer Prize-winning composer. Click here to read more about:
William Bolcom
Bolcom is also a pianist who frequently accompanies his wife, mezzo-soprano Joan Morris, in performances of American popular songs, ranging from the 19th century to contemporary songs written by Bolcom himself. (Click on some of the links at the bottom of the above page, if you want to read more about the Bolcom & Morris duet.)
Still no idea about mac's movie, though...