[CM] Snd setup

[Bill Schottstaedt]

After watching someone try to use Snd for the first time
(this person "never reads any HTML file", so the documentation
was a bust, and already knows C, so why learn Scheme), I decided
it's time to add a "preferences" dialog -- but the ones I've
seen strike me as a clumsy or useless.  Are there any good examples
out there to look at?  Or some better way? I also need to change
the default to make it more obvious which channel is selected, and
probably make "united" chans the default for multi-channel files.
Anyway, any and all ideas in this regard are most welcome.

(I was thinking of some buttons: "I want Dave's way" and "Do it
Kjetil's way"...)