The easy install worked on the temp basis, so I went with the live. None of the pages can be found, now.
Can I end the nightmare by simply deactivating the plugin, or will that make things worse?
Somehow, I fear my patience will expire before I get an answer.
EDIT: Never mind. I discovered that deactivating restores things to normal. Don't know what the problem was, but I'll consider this resloved.