And these lines are odd - you join strings with 'join' and '.':

  $filedate=join "", $Datetotal."damlbmp_zone.csv"; 
  $url = join "",'http://mis.nyiso.com/public/csv/damlbmp/'.$filedate;
  $filename=join "",$DownloadFilePath.$filedate;
[download]

You can simply quote them as one:

  $filedate = "${Datetotal}damlbmp_zone.csv"; 
  $url      = "http://mis.nyiso.com/public/csv/damlbmp/$filedate";
  $filename = "${DownloadFilePath}$filedate";
[download]