This box allows you to change your m600 drive to a Bafang stock controller firmware or change to the Luna custom firmware and then back again.
It will come with 3 different versions of firmware you can try including Bafangs latest firmware 14.6.
This box will not allow you to customize your own settings at this point... not even dealers are given that ability yet. However if Bafang decides to offer in the future for their firmware to be customized this box would allow you to do it.
Right now it is only good for writing different firmwares on your drive which will change the performance characteristics of the drive slightly with either bafangs or lunas custom settings. For example the amount of power in each pedal assist level.