First I think you are trying to do too much in your script. Try breaking down the functionality into smaller pieces.

See my MapDrive function below. Write a different function to analyze your group membership then call MapDrive with the proper parameters.
Code:
Function MapDrive($Drive, $Server, $Share)
    Dim $Drive, $Server, $Share, $shell
    Color c+/n

    If $Drive<>"" and $Server<>"" and $Share<>""
        $LogText="Connecting $Drive to \\$Server\$Share"
        ? $LogText
        USE $Drive /Delete /Persistent
        USE $Drive "\\$Server\$Share"
        If @error=0
            color g+/n
            $x=" - Success"
            "$x"
            If val($DOS) >= 5
                $shell=createobject("shell.application")
                $shell.namespace($Drive+"\").self.name=$Share + " on '" + $Server + "'"
                $shell = 0
            Endif
        Else
            color r+/n
            $x=" - Failed: Error @error"
            "$x"
            $ErrorState=1
        Endif
        WriteLog ($LogText + $x)
        WriteLog2("%temp%\MapDrive.log",$LogText + $x,1)
        Color w+/n
    Else
        WriteLog ("Function 'MapDrive' called with invalid parameters: '$Drive', '$Server', '$Share'")
    Endif
Endfunction


WriteLog() and WriteLog2() can be found in the UDF Library.
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