My solution -- of renaming the SLStore file -- turns out to be a partial fix at best. After I restarted Lightroom, I got the dreaded "Develop is not licensed" message when I tried to use the Develop room.
I shut down Lightroom and Photoshop, logged out of Creative Cloud and then shut down the Creative Cloud application. Then I tried to restart Creative Cloud. It wouldn't launch at all, so I restarted the machine. Creative Cloud started up again after restart, but went into "ever-circling blue wait cursor" mode, so I can't log back in or do anything else with it.
Restarted Lightroom, which told me that I would need to log in. I logged in as instructed. Develop and other functionality is now working again. After restarting Lightroom a second time (just to make sure) I still have Develop functionality. I'm not confident that it will last indefinitely, though. The Creative Cloud application is still unusable.
Dear Adobe, please take note. This kind of nonsense is why people hate Digital Rights Management and subscription-based software. If your implementation is anything less than rock-solid, you end up with a user base of very angry users who can't understand why they can't use the software they paid for. And that's not a good thing.