My computer arrived! Defying expectations it got in about 3 pm, instead of the 5 pm I expected. And I had time to start the setup. The biggest challenge of the setup was getting my Time Capsule password reset. At some point I changed it from the default I'd had when I was on my PowerBook G4, to something I guess more secure. It's surely something logged in the Keychain on my dead MacBook, where if there's a way to get it out I don't know. (I wonder now if I could have found a way.) Anyway, with physical access to the Time Capsule I was able to reset the password and get my stuff restored from it. This was a lot of waiting, some of which I was able to do out at Trivia Night in a restaurant near Flint with our pinball friend MWS and his family. (We won first prize again, cementing our undeserved reputation as the ringers.)
Not perfectly, at least. Not yet. There's a bunch of programs that I had gotten at one point or other and carried over from computer to computer and whose origin is now a bit of a mystery. There's other programs whose origins I know: they're on CD-ROM or DVD-ROMs. This will be exciting since the mid-2015 MacBook Pro I have is one of those that doesn't have an optical drive. I have a viable workaround for that, in that I can use my PowerBook G4 to make a disk image of the DVD-ROMs and store that on a portable hard drive I got for backup emergencies like this. It's stupid but for something I only need to do once (well, in one stretch), stupid is fine.
A bigger issue is that I had turned off Time Capsule backups on my photo and music libraries, probably because those took so long to recover. So I've had to go into single-user mode on the dead MacBook --- and that's still working fine --- and mount my portable hard drive to copy stuff over. This is also clumsy and a little stupid, but it's workable at least. Does mean I probably won't be ready to resume posting images from Pinburgh or the latter until after Sunday. Sorry. (In case you or a loved one has a similar problem though, here's instructions on booting a Mac into single-user mode and mounting a USB stick or external hard drive and copying what you need over. Hope you don't need it.)
And there's setting stuff up. A lot of setting stuff up. Most of my preferences didn't make the transfer over and so I'm going around fiddling with fonts and window widths and whether I want stuff to scroll like this or like that. It's exciting fun, certainly. And it's a good chance to rethink the stuff I'd been doing without thought for five years. But on the whole I'd rather not have had to deal with it.
Trivia: At the launch of a Saturn V the Apollo Guidance Computer began running Program 11. In the event that the Instrument Unit failed to guide the rocket stack correctly the crew could enter Verb 46, a command which would make the commander's Rotational Hand Controller joystick give instructions to the main engine rocket gimbals. This would allow for manual steering of the rocket into orbit. Source: The Apollo Guidance Computer: Architecture And Operation, Frank O'Brien. (It would be all but impossible to steer the Saturn V by hand well enough to allow a lunar landing mission to continue. This would allow for the Earth-orbiting contingency mission, the second-saddest consolation prize possible to an Apollo mission.)
Currently Reading: The Number Mysteries: A Mathematical Odyssey Through Everyday Life, Marcus du Sautoy.
PS: Happy wedding day 
chefmongoose and lovely bride! Best of luck to you.