Calibrating the instrument will not let users proceed to the next step due to the green check marks keep forcing the user to calibrate again.This will happen if the center dial on the device is pressed in when the rotary dial is been turned into the correct position which triggers the software to go back into a calibration mode. The easiest way to avoid this would be to keep the device out of the bag until you are prompted by the software to place it on the screen and then use the tips of your fingers or thumbs on the outside edge of the dial.