I feel your pain. I have a Singer Touch and Sew Model 750 and today it was giving me fits because it would not do much of anything other than a straight stitch. It would break thread, skip and drop stitches on plain old zigzag, as well as a couple of cam stitches I was trying to produce. I switched out the needle for a new one, and damn, if that didn't make the difference! No more dropped stitches, and no more skips, either. It seems like these fancy stitch machines can be very picky as to what supplies you use. I've gone so far as to name this machine Christine, after the car in the Stephen King novel LOL. She sometimes has a (EVIL) mind of her own!