Combobox background not being applied in windows 8

Question

I am a little confused with wpf themes. I would like to have the wpf screens look the same on Vista, Windows 7 and Windows 8. So I have styled the components accordingly and

Answer 1

Finally, after hours of frustration, I came accross an explanation post here. Scroll for the LONG ANSWER. It explains exactly the scenario I have been facing particularly Aero style not getting applied to my Combobox. The link explains very well why we need to add a BasedOn attribute to every element that we style if we dont want the default OS style being picked up. So adding this BasedOn for the Combobox got it working for me.