Charming

I bought this Fons & Porter Batik double wedding kit and today (like i always do) took a break from the quilt i am working on and grapped the kit to try one section or arc...i pieced and unpieced like ten times and i tried the pinning method and Ebony Love's method that she has a video on youtube and then i tried the curve master foot.....after all that what do i get???????????????
THIS.....

So my question if the notches of the melon shape met the seams on the arc then why did it pucker????
Any tips would be greatly appreciated.