[CM] Two minor bugs in snd-8 preferences menu

[Bill Schottstaedt]

Oh!  I see now -- there are probably at least 3 bugs in this
silly thing: the dialog should display the actual value of the
variable, the load-path needs to be set before the prefs file
uses it (duh!), and the 'save' mechanism should not assume
someone else is handling what it confusedly decides is a
default value.  Gad -- how could anything be that broken?

I still can't repeat the segfault -- I've tried to build a version
that is as close as possible to yours (we have different versions
of several libraries), but it's happy -- will poke at it further.