Thanks for the tips - I hadn't even thought about ironing different after the squares had been cut! After I had cut all my squares and worked with my layout they had gotten pretty wrinkled again due to playing around with them and some "helpful" cats. I sprayed them with water and ironed, not pressed, them again - whoops! That may have been part of my problem but I did re measure each square before sewing and some parts did need a little trimming ( but only by about 1-2 millimeters. If they do stretch a bit while starching, can I just re-square them up, or is the fabric ruined?
I'd consider trimming them down but I had *just* enough fabric to make the size quilt I have.