I'm so sorry you are having trouble. I don't have any advice that you haven't already been given. I will just share my experience. I quilt on a Tiara sit-down, so the needle is larger than on a domestic machine. I use Hobbs 8/20 batting, and I glue baste with Elmer's School Glue. I have done many quilts with minky backing, and the only brand I will use is Shannon Cuddle. I've had trouble with minky fabrics from Jo-Ann Fabrics - either the glue doesn't stick to them, or the nap comes through to the top. I actually had to tear apart the quilt sandwich and replace the backing with Cuddle when I couldn't stop the nap from coming to the top. I wish Cuddle worked that well for you. Also, I've never had trouble with the minky stretching. I just use plenty of Elmer's, and the backing never moves.