MFT – how to change what button clicks do?

MFT – Right now my MFT Button Click mutes my channels. But I want to change it to toggle the Effects Sends on or off. Or maybe even turn specific channel effects on or off. That would work too.

Basically I want to turn sends to audio loopers/echo on or off.

Do I change this in CSS or do I monkey with the Midi assignments in Live?

Thx!