Beautiful job quilting this. I bet your clients may have had better luck finding the pattern with the other name it is known by "Star Spin". Traditionally the center motif is surrounded by smaller star spin blocks like these
http://helpinghandsquilts.com/star-spin-quilt-pattern/
http://www.craftprojectspatterns.com...pin-quilt.html
It is also known as a strata star and several QB members have put up tutes for the center medallion. Here is one.
http://www.quiltingboard.com/tutoria...n-t101616.html
And here is a post that links to several tutes and some step by step pics
http://www.quiltingboard.com/main-f1...l-t207056.html