I migrated to a new blog engine, DotClear instead of OctoberCMS. This resolves the issues I kept encountering with comments being broken. People can now leave comments again, and they won't get lost in the ether.
However, in fixing one issue, I've turned up another, which is that some very old URLs are broken. I spent a morning trying to get Apache and Nginx redirects to solve this, and made some progress. All October links are properly redirected, but very old links from years ago before I installed OctoberCMS are still not working. My 404 page tries to help people with this. Your mileage may vary, depending on how good you are at heating gasoline before it gets to the carburetor1.
[Update]: Hey good news, this site rapidly regained the #3 spot in Google for the "infinite sphere" article even though the link slightly changed. Good to know their algorithm adjusts to minor URL changes like that.
Anyway, I like the new weblog engine. It has numerous improvements compared to the old; for example, search and archive work great! Only the blog works for now, and it'll take me a while to get categories and other such little things working. I'll add the other site pages when I get more time someday. That is all.
[Update] Oh wait, that's not all. I've been tinkering with DotClear now for a few days, making changes within the system and "beneath the hood" with stylesheets, low-level database imports/revisions, and tweaking all the configurables. I'm now comfortable with the system and I love it. It's the best content management portal I've worked with. It reminds me of WordPress back in the day before it became a monster. It is not only simple but powerful. It is obviously a labor of love by those who create it. Thank you. I've worked with more than a dozen of these, from the once-nimble WordPress when it first came out, to heavier CMSes and lighter flat-file engines, so I speak from experience: I'm impressed and heartily recommend this to anyone searching for a decent blog engine.
[Update] It took years to get to the point where comments worked properly, but I finally got all the comments working, or at least the ones I was able to salvage from various archives here and there.
Footnote: 1. When I was a teenager, I knew an old mechanical engineer who designed a preheater for the gasoline going to his engine, got 80 mpg from his car, but admitted it was an extremely dangerous hack. I thought he was the coolest inventor ever.