run the test application from the attachment to
On Windows the Window with the Change menu item is always behind the 2nd Window. The 2nd Window can be disabled, but stays in front. On ReactOS the 2nd Window goes into the back, when clicking on the first Window and goes back to the front when using the "Change" menu item in the first Window.
There are other cases where the z-odering doesn't work as it's supposed to.