Instead of looking at it as sashing, can you add the pieces to each square, thinking of it more as each square having a border and then put the blocks together. Adding the short side to the block first and then the long side with the cornerstone. It's really hard to help without pictures. I'd love to help you brainstorm. Sorry you're feeling so frustrated. You can pm me if you'd like.
Last edited by tlambing; 12-08-2014 at 06:13 AM.