I had the model that was right below this. The Ice button would simply pull the top ice shelf out with the door/drawer when you pressed it while pulling the handle, IIRC.
The auto-fill tray worked with a weight switch that would actuate the water valve circuit when the tray was empty. You tipped the freezing tray over into the bin when the ice was frozen and after closing the freezer door, the tray would refill.