The position values in the AKD Basic drive are in integer format. It does not have the usual "3-decimal-place" floating-point value. So when defining the user units, make the resolution fine enough for precise positioning. If the units are defined as "inches" and the scaling is x number of inches per motor rev, then it will only be able to position to the nearest inch. It will not be able to command a move to a fraction of an inch. Multiply the scaling by 1000 to program in thousandths of an inch. Just remember that the units are now "mils" or "0.001 in".