Thank you, that satisfies my curiosity. I don't blame you for moving on to a new version, which I'll upgrade to when I move up to El Cap.

I figured it had something to do with a change in the Mac OS. One of the things that I find crazy about "OS X" (again, neither here nor there.. just whining)  :@  😄 is that they have made a ton of major changes that should have warranted a new version the OS. For example, the move to Intel should have moved OS X up to OS XI (Eleven), and so on. You doing a re-write of Cookie's code warrants a version change (rather than an incremental version update to Cookie 4). When Apple issues an update of OS X, it's hard to tell if it's a just a few tweaks here and there, or they've thrown the baby out with the bathwater.

Anyway, thanks for responding, and thanks for putting up with my off-topic whining about Apple.  😛

Thank you very much, Russell, the delete and re-install method worked for Cookie, and one other app that (after I posted) did the same thing.

A more recent article on iMore explains what happened and includes an update:

Here's What's Happening