A question for you. Do you set the seam before opening it up to press? I have found that this really makes a difference. Also, are you pressing it or ironing it back & forth? I never iron mine. I just press it with one swipe & then up & down motion. I never move it back & forth on the seam as this will cause the seam to separate just a hair. Although, after your quilt is finished & you wash it, all should fall back into place.