I appreciate the link. I read that just a few days back while working on this, but I feel I have more fully grasped it this time. It appears to indicate that each codepoint, or range, should terminate with a newline character--something that my present code is not doing and which your revision does.

However, when I replaced my code with yours, it effected no change--the second test still fails. Is this mysterious? or can it be rationally explained?

As I said, I seem rather "gifted"....