@klauss & mecho

Thanks once again for your patient tutoring of this rank amateur.
mecho's quoted experience and klaus' quoted reference help a lot.

I can't help noting that I find this 'urgent' thing pretty well
hidden from view. Seems like an appropriate icon in Synaptic
might make this urgency a lot more obvious.

I am encouraged on both fronts to upgrade LXDE at least for the
three elements noted in my post #2. I've saved my current .img,
just in case things don't go well. I'm hoping this may remedy
my PCManFM gripes.