Checking your backlash should be no problem if you have an indicator. Put the indicator on something solid. Jog your axis until you move the indicator to a reading of about half of its travel. Write down the reading on the indicator. Jog the axis in the opposite (This is very important.  Backlash will only show up when you change direction or bouncing from tool load.)direction by a set amount, say .010" and see how much difference the indicator shows. If the indicator says you moved .005 and Mach says it has moved .010 then you have .005" backlash (assuming you have not skipped any steps while testing).
 
Brett