Thank you very much for your response.
Yes, I have an Adobe ID, and yes, I registered my copy of ADE with it.
I did try the Control-Shift-D procedure, but it did nothing.
You're correct, it's extremely hostile. The problem is that I downloaded this program to be able to read books through Open Library, as my local library charges a fortune for a library card, so I have no access to a library of any kind at the current time. But it looks like I'll still be unable to have any avenue to check out books, because Adobe offers ZERO tech support for their product, and I haven't seen any answer yet that resolves this problem.
Thank you again. Considering you're doing the work that Adobe should be doing to support their own product, even though this didn't work for me, I'm still going to mark this as "helpful," since you've done a lot more than Adobe has done for me!