Maybe this would be much simpler if the user just configured the ratio units required to reflect the desired units in volts, milli-volts, etc, and then calls the voltage units by another name such as amps, pressure, strain, or what-ever units. Then the Nano can stay with voltage units displayed. For example for 10mv = 100ma, then the user just selects a probe ratio of (1 input unit = 10 out units) probe ratio and the 10mv would convert to 100mv and the user would call that 100ma, or in other examples other 100m-Units.
Just another discussion of the feature.