A tip for setting perfect zippers - position them precisely how you want with glue! Line up your ends, and any details floating across the middle, and use a water-soluble glue (I use Tacky) to set it exactly where you want. Once the glue is dry you can sew it right into place and it won't move or shift around. It also helps to press your seam allowances under before gluing. In this case I did the lining separately on the inside, too. Once both sides were set with glue, I stitched the zipper in place securing the fabric and lining all at once.
