I'd very want to add several more attributes (or columns in DB terms) to audio files on OSX. I've read the manual here but it states that: "Only one importer is allowed per uniform type identifiers (UTIs)." There is an identifier for public.audio UTI, so technically my importer cannot work.
However I suspect there should be a non straightforward way how to achieve this, probably via declaration one more UTI class or by chaining my importer before a system one. Any ideas appreciated.