That is looking good Bev.
Do you have any more squares that you haven't put sashing around? If so, you could put sashing at the top and the bottom then sew them to these blocks you have done then you would only have 1 sashing between yours blocks. I'll see if I can come up with a picture.
Hopefully I explained myself.
Yours will definitely look better than what I layed out here. I was just trying to give you an idea of the concept.