The various versions of Micro$oft Word that I've used allow one to select which convention is accepted by default. As a user in Oz I've learned to root out all the US versions of dictionaries if I wish to type undistracted by attempts to change my usage. It's not much good substituting (what Micro$oft calls) "Australian English" either, as the programmers seem to believe we're all honorary Americans. I have to select "UK English" to achieve some accord with what I was taught at school, where I was also taught to honour conventions until and unless they led to confusion, when they were to be avoided.

Cheers, Rowan