Third Button on CA3 Digital AUX

Configuring my first Ebike build. It's a hub motor, Phaserunner, CA3 setup. I have the 3 button digital AUX add on. It's presently configured to switch Presets using the top and bottom button.

Is there any way to use the middle button? I want to both switch Presets and adjust PAS sensitivity. Hopefully without adding the second analog pot device. A simple 1-2-3-4-5 level then back to 1 is fine.

Or perhaps better, use the middle button to do presets and the top/bottom for PAS.

Is this possible?

Thanks!

For anyone else looking at this question....the answer is the middle button isn't connected to the CA3 interface. There are two hidden wires under the shrink wrap to use it as a SPST momentary switch for anything you can dream up.

I ended up with PAS sensitivity on the +/- buttons. And switch the presets using the buttons on the CA3 itself. Works OK.