OK, I'm back. The first sign of success was a local login prompt after install. W 10 did not ask me for a Microsoft Account. Surprised. Three minutes of waiting after hitting Enter at login page (1.6 GHz C2D U9600, but with 128 GB SSD) for the two subsequent pages.
The "Hi" stage now is pulsing blue shades, not a rainbow like 8.x. Just received a full page "Unfortunately, it's taking longer than usual" message. Never have seen that before, but not surprised that it's happening on this machine. That stage took about 5-6 minutes.
Screen went black, cursor still works. This lasted until I figured out that explorer.exe (shell) hadn't initiated. Ctrl+Alt+Delete - Task Manager - Run New Task fixed that. All of my pinned icons are there.
Now for a shut down - restart to see if it stuck. It did. Asked for Ctrl + Alt + Delete to allow for login, just like before. Everything is there on boot. Yay!