It would be awesome if this extension support w:numbered musical notation, which are widely used in Asia, although it's never been popular in the West. There's a Lilypond hack for it:
Topic on Extension talk:Score
If Lilypond itself does not support it, it first needs to be supported in Lilypond. You can file a request for Lilypond developers at http://code.google.com/p/lilypond/issues/list