I fight this error almost every time I go to contour cut something. What I have found to work for me sometimes is to turn off all the lights in the room. Yes, its a pain but hey it works.....sometimes. Another thing, if the prints are laminated, try cutting the laminate from around the registration marks, apply transfer tape over the marks and then re draw with a felt tip marker or fine tip sharpie. Also, sometimes scotch tape works but be careful that the sensor reads the mark and not the edge of the tape. Last, go into your ARMS settings and see what your mark scan levels are set at. Ive had to turn mine x, and y, up to 90. I don't know what the real issue is but its very very frustrating and I haven't been able to get any answers on how to fix it. Ive done the tests with using the pen tool and drawing the lines out and making sure everything is aligned but my contour cuts are still off most of the time. Wondering If its a firmware issue but haven't been able to get confirmation on that either. Good luck!