Sets the WatermarkBrightnessPortrait member of the BlackIceDEVMODE. The nBrightness member stores the Brightness Value
SetWatermarkBrightnessPortrait(pDevMode As Long, nBrightness As Long) As Boolean
Input value:pDevMode - handle to the BlackIceDEVMODE structure.
Input value:nBrightness - Brightness (Long)
Return value - TRUE on success, otherwise FALSE.
NOTE: For 32-bit applications, use pDevMode as Integer, instead of Long.