First off your quilt is beautiful, secondly no no quiting quilting...I'm no expert and quite new myself...Currently I have a quilt loaded on my longarm and one waiting...so I thought get the back ready for the second quilt and it will be ready to go...hummmmmmm yeppers on my second quilt, I have the wave going on...How can this be I was sooooo careful, well apparently not :oops: So I smoothed out the quilt as best as I could on the rug, started at top border pinned the first corner down continued to the other corner...laid flat...same with bottom one...on to the side borders...hummmmm yeppers they aren't laying flat noppers...so off they came. I remeasured and I was out...fixed it...found the middle of my quilt sides, border sided and matched...then pinned all the through the side borders...lots of pins...back on the floor it went, does it lay completely flat...well not perfectly but I will be able to quilt it without any puckers.. If you really aren't happy, do like I do, and just take the borders off and remeasure....