Implementing developer tools and PID tuning

I've just switched from an ASI BAC800 to a VESC 6.6 on my ebike. So far the VESC is working well. But I'd like to be able to field weaken as on my ASI. How does one implement this experimental feature into the app or pc VESCTool? When I import XML files into the developer editor, nothing shows up in the VESC tool itself. A step-by-step would be helpful. Also, I'd like to tune the PID. A step-by-step would be helpful for that as well. Anyone have any links? So far my searches don't turn up much. Thanks.