I don't know anything about the original handi quilter frame. Sorry. But, I can't imagine that it is much different than the handiquilter II. When I clamped down the L-shaped sides, I put the clamp in the middle of the L instead of at the end because of that same reason. Maybe if you measure every 1/2 inch or so, and mark this on the side arms, you will get the arms to be even. This is a pain, but it worked for me. Mine would slip down and then I had to tighten it with the black star knob but I used those lines to level both sides. Also, when I had the HQ II frame, my poles were very flimsy, so my hubby bought some heavier poles,one long pole and put the original poles inside them and then screwed them together at the ends to give me a more solid pole. Maybe your tracks aren't straight and that is why the bottom carriage doesn't stay on the tracks. What do you have your frame mounted on? Mine was mounted on one of those 6 ft folding tables. Good luck I hope this helps some.