Hi Robert_U,
Thanks for the driver update, and the detailed post explaining what's new.
I'm afraid that the issue DirectX 10/11 games running in centred mode in fullscreen (Windows 8.1) does not appear to have been fixed on my system (i7-4500U with HD 4400, 64-bit).
Also, further to reports made for previous drivers (which you have kindly noted in the past), this driver still has issues with shaders in pre-DirectX 9 games (e.g. No One Lives Forever).