Thanks Mark, I have installed all of Ken's new header files (and top.php, and common.php, etc).
I've gone back and made sure that all Ken's script are up to date, that I have latest version of the gauges, that WeatherCat is sending the right info (v1.2) and that everything is installed properly. But something is clearly out of whack.
The key symptom is that the UTF-8 functions are being ignored as evidenced by an ? (C3 85) before the temp gauge units. Everything else seems to work except the units radio-buttons selection are reset to Centigrade on each new data update. (Actually the buttons don't change, but the gauge display reverts to Centigrade).
I've tried to follow the process using Apple developer tools in Safari, but not being a developer I'm fascinated by, but ignorant of, what it's trying to tell me.
Oddly, the same problem occurs even with the included .htm file.