A Graphical User Interface (GUI) for an external device used to program an implantable stimulator device is disclosed. The GUI includes aspects useful in adjusting the current magnitude provided at one or more of the stimulator device's electrodes. In particular, the GUI includes an amplitude slider, which allows the user to slide an indicator to increase or decrease the current magnitude at different rates depending on the length of the slide. The GUI further allows the user to prescribe drop back functionality, which reduces the current magnitude by a prescribed amount when the indicator is released. In one example, drop back functionality can be engaged in accordance with a rate threshold, and thus drop back functionality will only occur when the rate of increase equals or is above the threshold when the control button is released.