Well, it's a workaround at best. I still haven't got global control of Office that FIXES it to UK English.
As mentioned, an automatic download from MS on 2007 fixed the problem in a jiffy.
Clearly, the dictionary is in 2010, since I can 'select' the text and use UK English. It really does smack of the soft being corrupt but it's had time for updates.
I'd assume it was me if it weren't for folk on forums bemoaning the same fate.