The plugin updates that don’t require backing WP to previous versions made the second site conversion much easier. I think I interrupted the process, however, and it took a very long time before I could get it going again. This site is in English, so I probably should have started with it.
Will think about the subscription plugin. This is such a small site that I may go without it. More of a commonplace book spot for me.
And the post-by-email plugin, which was way over my head, may also fall by the wayside.
Celebratory post after CP installation:
Thanks to all who made this possible. Makes me feel much lighter.