Following script shows a parent GUI with a child GUI initialized as MDICHILD.
#include <Constants.au3>
#include <GUIConstantsEx.au3>
#include <GuiReBar.au3>
#include <GuiScrollBars.au3>
#include <GuiToolbar.au3>
#include <ScreenCapture.au3>
#include <ScrollBarConstants.au3>
#include <WindowsCons...