Miriam,
I have one maybe two of those Greist blind hemmers. One is for a top clamp Domestic and the other is a low shank. I have different instructions than you do though.
I also have one of the Greist ZZ attachments with the little star cams but I can't find it. I don't think I have any instructions with it, but I can't be sure until I lay my fingers on it.
These are some neat gizmos that's for sure.
Joe