SJ--First off, excellent job on this machine! Have you solved the problem with the balls sticking in the rocker yet? I had a similar problem on one of my machines. It turns out that the center attraction had some slight warping causing a part to stick. I solved it by removing the center attraction, putting slight pressure on the plastic in the direction it needed to go to correct the warp, and gently heating with a heat gun at a low setting. The plastic will soften, and when it gets to where it needs to be, remove the heat, and hold it in that position until it cools.