Expression Pedals & Boss RC 300

Could anyone point me to an existing patch that ‘attaches’ an expression pedal to function (as one would a knob)?

I also saw this old thread from about a year ago that makes it seem that mother.pd needs to be modded to get the M-audio Exp to work. That seems scary. Paging @jhindsight, are you still rocking with the pedal a year later?

Would the Roland EV-5 work without that type of mod? This is all very new to me, sorry for all the questions.