Just a few comments:

• I assume that this:

  if (!$ARGV[0]){
      print "Input File:\n";
      $fn = ;
      chop($fn);
      }
  [download]

  was meant to be:

  if (!$ARGV[0]){
      print "Input File:\n";
      chomp($fn = <STDIN>);
      }
  [download]

• I think that $par = $_[0]; is beter off to be $par = shift;
• <.*script.*> is greedy
• what's that? $par =~ s/\"/\"/g;
• There's a lot more with the regexes but I won't talk about that anyway...
• while ($nl=) is missing the <INF>
• $cl = $cl.$nl should be substituted with $cl .= $nl
• $cl = ""; is better as undef $cl
• a lot more in the coding, now I know TIMTOWTDI but some ways are more efficient, and after all you are using perl, so you should use it.

Good to try new things, but try to improve your coding skills by looking at other codes, and analysing them.

Improved, but not by much