Hi Alberto,
totally great! Really a role model for ther kinds of "user library" patches people could be uploading. I also really appreciate the docs. This is the kind of thing I would show at the beginning of a workshop for people to see what is possible.
A couple things:
interpolating the panning values at audio rate in "panner.pd" with a [line~]. You've used [line] or [line~] just every other place that I can find, so that looks like the only place the clicks would come from.
a real math geek! ;-) What might help this patch to have more educational value would be to put comments about what all these expressions are doing. But that's just my two cents.
Thanks for posting this, d.