Yay!
When I opened up Dominions, after re-installing it, I noticed that there were still saved games available. "Aha!" I said, "how is this possible?"
So I seached my hard drive for files or folders with the name "saved" and lo, what should I find but an entire Dominions3 Folder with a maps folder and a mods folder that no documentation or message ever told me it created.
And here I had created my own such folders thinking I was doing exactly as I should.
So I moved the mods and maps over to the newly found, but original, folders... and voila! It all works as it should.
Man... I was hunting down some really obscure trails. But I know a lot more about the various text editing endlines than I did yesterday!
So for those of you with Macs, search your hard drive for the dominions3 folder before you create your own. You just might be surprised.
Happy ending.