#include <GUIConstantsEx.au3>

Example()

Func Example()
        ; Set the title of the AutoIt Hidden Window.
        AutoItWinSetTitle("My AutoIt Window")

        ; Display AutoIt's Hidden Window.
        AutoItWinShow()

        While 1
                Switch GUIGetMsg()
                        Case $GUI_EVENT_CLOSE
                                ExitLoop
                EndSwitch
        WEnd
EndFunc   ;==>Example

; Display AutoIt's Hidden Window. Returns the handle of the window.
Func AutoItWinShow()
        Local $hWnd = WinGetHandle(AutoItWinGetTitle()) ; Get the handle of the AutoIt Hidden Window by finding out the title of the AutoIt Hidden Window.
        WinMove($hWnd, "", (@DesktopWidth / 2) - 250, (@DesktopHeight / 2) - 250, 500, 500) ; Move the AutoIt Hidden Window and re-size for a better view.
        WinSetState($hWnd, "", @SW_SHOW) ; Show the AutoIt Hidden Window, normally this is hidden, but in the interest of this example I'm displaying it.
        Return $hWnd
EndFunc   ;==>AutoItWinShow