More good help from Manton, cleverdevil and others, but alas no nearer (although I may have eliminated some possibilities).
- I was allowing both HTTP and HTTPS. There could have been some kind of mismatch, I suppose, but after editing .htaccess to force SSL, it made no difference to micro.blog's OS X app.
- Then thought that possibly a different endpoint would help (despite the fact that I know all the same details are on the home page).
- Pointed micro.blog first at /profile and then at /profile/jeremy; still no good.
At this stage, given that Manton managed to get everything working from a clean install of Known out of the box, I think I need to try the same. If that works, well, if nothing else, it works.
I had been fretting about losing data, but if I install into a new sub-domain and it works there, I can always edit the config.ini to point back at the old database. It will be a good opportunity to see how good the instructions are to install at Dreamhost. Last time I managed without any instructions, and I also didn't write up my experiences. This could be an opportunity to pay back.