| DirectX SDK | 
The DirectDrawSurface7.UpdateOverlayZOrder method sets the z-order of an overlay.
object.UpdateOverlayZOrder( _ 
    flags As CONST_DDOVERZFLAGS, _ 
    ddS As DirectDrawSurface7)
If the method fails, it raises an error, and Err.Number can be set to one of the following values:
| DDERR_INVALIDOBJECT | 
| DDERR_INVALIDPARAMS | 
| DDERR_NOTAOVERLAYSURFACE |