Check out You Tube and Jacquie Gering videos. Very helpful for straight line quilting.

Linda, I don't have an answer but do share your frustration. No matter which machine I'm using I can't get straight lines with a walking foot.

I did not get along well with my walking foot (we have never reconciled)! I loosened the presser foot - how firmly it holds the fabric as it feeds through and dropped my feed dog a bit- not 100% completely down. And it stitched beautifully for me front and back. I was using an old Singer 15-91 so not same machine as yours. If on domestic machine I pre-marked the lines because I would get lost as the quilt get wadded up and rolled and re-rolled just stuffing it through the throat! And even on the longarm I have pre-marked some
https://www.youtube.com/watch?v=SVIjP5tn_5U

The skipped stitches is maddening for sure!! When you're not under the gun for time I'd experiment with adjusting the machine on the frame and try different ideas. Maybe you have better success going one direction vs the other.

Hello Onebyone....I did buy a 1 1/2" metal carpenters ruler from Harbor Freight and managed to do a cross hatch pattern on my latest project. I also remembered that a very wonderful woman gave me a 3/4" square block yard stich years ago and I'll be using that to mark the quilts with Crayola Washable Markers from now on. Thank you for opening my eyes to a very simple soultion!

I also mark about every 8"-12", being sure I am also staying parallel to any piecing seams at the same time. It's easy to start getting slanted as you go along.

Watson