there is no clear way to adjust backlash without using a dial indicator and physically measuring the lash on an axis, so this step should be removed from the OHAI.
if the circle is out of round i would recommend cleaning the nozzles really well and run another auto calibration
if the machine backlash setting is too low, there will be uncompensated backlash left in the system.
if the machine backlash setting is too high, there will be overcompensated backlash added to the system.
Calibrators should only rely on the auto cal for backlash measurements.