Oy!
The help pages show:
*Account Settings*
Copyright Statement
Technically, all images are automatically copyrighted by the photographer. If you would like a specific copyright message to be displayed at the bottom of the image screen, you can enter it here. This same message will display for all of your images. You can override this copyright statement at the gallery level using the advanced gallery settings.
Which implies it works as I suggested in my previous post. The (former) engineer in me wants to test my theory, but if things are in fact, screwed up, I'd hate to subject myself to possibly wading through 547 galleries to change something after I mess it up!
According to my dubious theory, making a change from Edit Root gallery should only affect images in the root gallery -- or perhaps in a new sub-gallery created after the change. I've noted that some things (number of thumbnail columns is one) are inherited by the "child" gallery at the time of its creation; but they can be overridden by editing 'Gallery details' in the new child gallery.
(This is part of a PBase anti-Alzheimers program designed to exercise our brains with puzzles!
)
DaveT