I do not know much about digitizing but a thought crossed my mind when making up some zipped purses for a fete.
I find that a zip goes in much easier when following a center stitching placement line rather than parallel lines for the zip to fit in. Our South African zips must be marginally a different width. Just a thought.
Yes, you are correct. The zippy bags I stitch out are by Anita Goodesign and that digitizer gives you the zipper box and the center line. it is so simple.
Good point. I usually put both in my designs when the zip has to be stitched to the stabiliser. Not for the easy zip purses though as it isn't necessary.