I think it really is a horror film in the complete sense of the genre as there is no 'safe home' at the end and endless 'personal identifiers' in it. A superb film. I'll have rummage around and see if I can find anything out about the music. It seems to have phrases from every folk song or tune you have ever heard, which is another element of horror genre - the audience being able to identify with key elements, in this case the music and the traditions which go along with them.