Sorry, after more searching through the list,
I came across Mihai Basa's post:

>To install it for testing you need to:
>1 - copy it to ~\.kde\share\apps\katepart\syntax\
>2 - (optionally) delete
~\.kde\share\config\katesyntaxhighlightingrc
>    which is a sort of cache, 
>    and sometimes keeps the old highlightings.

And sure enough, the cache file was the problem.
Thanks for reading, 
George Moudry


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