I think there is a problem in capturing child windows (e.g. settings of firefox) with Aero-transparency when they are in front of their parent-window.
When child windows is in front of its parent-window the content of the parent-window is still captured in the border of the child-window.
When the child window of a not maximized application is positioned over another window (or desktop) the content of this window is not captured in the border.
When the child window of a not maximized application is positioned half over its parent window and half over another window (or desktop) the content of the parent-window is still in the border, the content of this window not.
The black-white flashing works only over the other window.
All my settings for "window capuring 1" and "window capuring 2" are on default, I also tried with a fresh unziped portable screenshot captor.