I know only a little about Slavic myth, chiefly just the bits where it brushes up against other mythologies I know better, or what I've got from various bits of fiction, and I think it may be useful to rectify that.
Were I not required to be in the office on Friday, I would be here. If you are in London, and do no have anything pressing to do between 11am and 5pm on Friday, I strongly suggest you go. And take notes. Lots of notes. And then give them to me.