Make sure that you have the weight of the quilt supported. I had the same problem and when I made sure that the weight of the quilt was not dragging down things went well. I spent 2 hours ripping my mess out.
I read on this board that someone else had the same problem and they turned their sewing machine on its side which is what I did. I built up either side of the machine to support the weight.
Good luck with it.