Here a modification of your GraphGDIPlus UDF.au: #include-once #include <GDIplus.au3> Opt ("GUICoordMode", 1) Global $aGraphGDIPlusaGraphArrayINTERNAL ; #FUNCTION# ============================================================================ ; Name...........: _GraphGDIPlus_Create ; Description ...: Creates graph area, and prepares array of specified data ; Syntax.........: _GraphGDIPlus_Create($hWnd,$iLeft,$iTop,$iWidth,$iHeight,$hColorBorder = 0xFF000000,$hColorFill = 0xFFFFFFFF) ; P