So, I got it working, but it wasn't easy. First I put on the monogramming foot instead of the walking foot; not sure that helped at all. Then I saw that I needed to really encourage it to move forward during the forward part of the stitching, and stay in place when it was sewing in place--I slowed down to the lowest speed possible and counted out the forward moving stitches as I pushed slightly, and counted out the in-place stitches as it stitched in place. Whew!
I don't understand why the feeding didn't work right even with a stabilizer, but it's done, and I'm happy now.