Well, I'm narrowing it down, so I deleted two earlier posts. It AIN'T Windows 7, and I don't think it's lack of updating Creative Cloud, since I rebooted after that...
In InDesign CS6 all 32 sub-fonts under Myriad Pro show up, and are usable.
If I copy them into my newer InDesign CC, twenty of them disappear, and are not accessible! [See screenshot]
I can understand why the newer InDesign CC might support fewer fonts, but if I open up InDesign CS6 on MY SAME COMPUTER, at THE SAME TIME, I can still see all 32 of the Myriad Pro sub-fonts, and use them without problems.
But I've searched "everywhere" on my system, and can only see the 12 that CC uses. Any ideas?