with some modifications it works, thanks!
based on the choices made in the gui this will send those choices as variable to a second script and then execute.
#include <GUIConstantsEx.au3>
$b = True
If $b = True Then FileInstall("C:\addtogroup.wsf", "C:\Temp\addtogroup.wsf")
Opt("GUIOnEventMode", 1)
Local $Btn, $Btn2
Local $hGUI, $Combo
Local $msg
Local $sCombo2test, $slp1text, $Combo2, $Input
$hGUI = GUICreate("Add_User", 400, 400)
$Combo = GUICtrlCreateCombo("server01", 10, 12, 200, 25)
GUICtrlSetData(-1, "server02|server03")
$Combo2 = GUICtrlCreateCombo("Administrators", 10, 124, 200, 25)
GUICtrlSetData(-1, "Guests|Users")
$Input=GuiCtrlCreateInput("domain/user", 10, 236, 200, 25)
$Btn = GUICtrlCreateButton("ADD", 300, 24, 70, 50)
$Btn2 = GUICtrlCreateButton("EXIT", 300, 284, 70, 50)
GUICtrlSetOnEvent($Btn, "ADDButton")
GUICtrlSetOnEvent($Btn2, "EXITButton")
GUISetState()
Func ADDButton()
$sCombotext = GUICtrlRead($Combo)
$sCombo2text = GUICtrlRead($Combo2)
$slp1text = GUICtrlRead($Input)
Run ("cmd.exe", @Systemdir, @SW_MINIMIZE)
WinWait("[C:\WINDOWS\system32\cmd.exe]", "", 30)
$sCombo2text & @CRLF & "Combo contains" & @CRLF & $sCombotext)
ControlSend ("C:\WINDOWS\system32\cmd.exe","","","Cscript c:\Temp\addtogroup.wsf /s:" & $sCombotext & " /g:" & $sCombo2text & " /a:" & $slp1text & @CRLF)
WinWait("[C:\WINDOWS\system32\cmd.exe]", "", 30)
ControlSend ("C:\WINDOWS\system32\cmd.exe","","","EXIT" & @CRLF)
EndFunc
Func EXITButton()
Exit
EndFunc
While GuiGetMsg() <> $GUI_EVENT_CLOSE
WEnd