Thanks all but especially Howard, that clarifies what I thought. The other tune that I have used is Eddie Cochrans Summertime Blues - which I have rewritten as Autoharp Blues. Since it might be a bit problematical contacting Eddie to ask for permission, I guess I will not be distributing this one, just doing it in my gigs and letting PRS sort out who gets the royalties for it. I still have lots of questions - when does an arrangement become an adaptation which needs permission, how much does it cost me to add download rights, and is there any inherently let in recording the stuff in the USA and then producing in this country, for instance? But I know who to contact about these. As for my own royalties, I am betting that what I get back will be a lot less than the registration fee. I am much more concerned that artists like Richard Thompson get adequate compensation for the humiliation I cause by covering their songs.