I have the 1600P on a handiquilter frame. Mine is very picky about threads. In fact the only thing I have had luck with is Mettlers thread , a topstitch needle, set just shy of 3 on tension with bottom line in the bobbin. Skipped stitches are typically caused by your encoders. Be sure that your track is free and clean of lint and dust. Good luck and just keep playing. I found it easiest to make a journal of what worked and what didn't.