EVSEUpgrade also either re-programs or replaces the circuit in the brick, as the lights behave differently on their newer units.
To adjust the amperage, insert a paperclip into the proximity and pilot pins on the J1772 handle. The red Error light on the brick will start flashing rapidly. Then, simply click the release button the desired number of amps you'd like to charge. Each button press will flash the green light once (10 flashes = 10 amps), up to a max of either 12 or 13, based on voltage. When you've reached the desired amps, remove the paper clip, and count the flashes. If the amps are set to your liking, click the release button once more, then plug the car in. This resets to default after unplugging.
They also mention a way to override the GFCI for emergency generator charging, but I think you have to contact them to enable it to minimize abuse.