You absolutely can post pictures of the quilts YOU have made. Once the pattern is sold to you, what you do with your quilt is up to you totally. That's part of what the designer sold to you. What you cannot do is copy and sell or give the pattern to someone else. Nor can you claim it is your design. I have read that it is suggested when you display a quilt in a show or wherever, that you give the designer's name and/or the manufacturer of you have used one group of fabrics from a specific manufacturer.