I have had similar problems when quilting something after using Lite Steam-a-Seam 2 for the applique. I stopped frequently to wipe my needle down with alcohol. I tried the non-stick needles, but it didn't seem to make any difference for me. Keeping the needle as clean as I could solved most of my thread problems, but it took forever to quilt. Trying to look for an answer, I found that I probably didn't apply the iron long enough to melt the adhesive into the fabric, but I don't know if that would apply to your basting spray or not. Maybe test on a scrap before using again?