You might need to raise the item to be marked up into the correct range, especially if you are not using the tray. There is a diagram and discussion on working without the tray here:
Keep in mind, you can now use the Set Focus tool instead of doing the calculations, but you still need to prop the surface of the material up into the correct range, which measures from 1.4" to 1.9" from the metal plate in the bottom of the machine. If you are working on top of the tray it’s not an issue, but the item needs to be less than ½ inch thick to put it on the tray.
Also, if you haven’t run the Calibration Program yet, you’ll want to do that first to set the calibration for your individual machine.