Thank you everyone!
I should specify what happens when I enter the code for the second or third of fourth gallery: it will only display the FIRST gallery, and the others are displayed as the CODE
[nggallery id=X] right under the last pic in the FIRST gallery.
OR, I try again on another page, and as soon as I click SAVE, the first gallery no longer SHOWS THE PICS (it just has "picture 1" "picture 2" markers where the pics were SHOWING before!) and the newer gallery id DOES SHOW.
It's so weird!
Something must happen to the existing gallery (first one) when I cut-and-paste the gallery id code into the page and hit save. But I have no idea what happens to it.
thedrewseum: Wow, your site is beautiful! And that is what I need: just like you have it set up. You are using the NEXTGEN Gallery plugin, right? Just to check. And you stick in the code (above) and it works for you?
This is so odd. Maybe you are using an old version of the plugin that allowed the multiple galleries to show on a page or post?
Thanks so much for posting your info!
carpetguy: Thank you, also! I will keep working on getting to the bottom of this.