The Sled and the rack have too much Tolerance which causes the notches of the sledge to disengage. I was too lazy to redesign the Sled or the Rack, so I made this adapter. Recommended layer height 0.1-0.2mm and add a support blocker to the notch. If you can, just make the sled bigger by a total of 1.8mm to make the original design work.
One Adapter per Disk slot is enough to fix the tolerance.