I have an interest in using one of these types of controllers in the future, so I had a look through the documentation using this as an example problem. I get the impression that not all parameters are changeable 'on screen' and that you have to load a parameter file to your computer, edit it and then upload the parameter file to the device. If this is the case then it seems a lot of faff, I would assume that future versions of the firmware might include the facility to edit this parameter directly as well as the much desired twin screw axis homing and squaring. I don't know how much of the world other than USA (and model engineers stuck in the past) operates in imperial measures, but I reckon it could be a poorly implemented afterthought to make some gesture to the non-metrics of the world.