Now I may have got this wrong, but I opened the Desktop Application Manager (DAM) today, for no other reason than to check the version number for a thread in this forum, and without thinking about it, I told it to go ahead and install updates for InDesign and InCopy. The thing is, I hadn't bothered to open the DAM in Administrator mode (Windows 7) which would normally mean the update would get half way and fail.................but it didn't! (I've been watching reruns of Top Gear, and seem to be talking in Jeremy Clarksonisms ).
I'd already noticed that I no longer have to trash App Data\Local\Adobe\OOBE\opm.db every single time I wanted to sign in to the DAM, since the last update, so things are looking up. A week from now, Adobe will announce major updates for all the Creative Cloud apps, so fingers crossed they don't introduce another round of bugs to be fixed.