Try:

open(STDOUT, ">>$logpath") or die "Cannot redirect STDOUT: $!";
open(STDERR, ">>$logpath") or die "Cannot redirect STDERR: $!";
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Any errors or screen output therefore produced will be pushed to $logpath.
You might also find this section of code handy:

use Net::FTP;
  # lets seperate any URL from the hostname
  ($host,$url)=split('/',$data{'FTPUrl'},2);
  $ftp=Net::FTP->new($host,Debug=>1);
  $results=$ftp->login($data{'FTPUsername'},$data{'FTPPassword'});
  print "Mesage: ".$ftp->message()."\n";
  if (!$results) {
   $failedlog.="* Unable to login to remote FTP site ($host) with\n";
   $failedlog.="  Username: $data{'FTPUsername'}\n";
   $failedlog.="  Password: $data{'FTPPassword'}\n";
   $failedlog.="  Error:    ".$ftp->message()."\n";$failed=1;
   print $failedlog;
  }
  print "Logged on using $data{'FTPUsername'}, $data{'FTPPassword'}\n"
+;
  if (length($url)>1) { $ftp->cwd($url);print "Changed to $url\n"; }
  $pwd=$ftp->pwd();
  print "CWD is: $pwd\n";
  $ftp->hash(STDOUT);
  $ftp->binary;
  print $ftp->ls;print "\n";
  $results=$ftp->put($filepath,$filename
  if (!$results) {
   $failedlog.=" * Unable to uploaded $advert{$i.'-Advertname'})\n";
   $failedlog.="   Error:   ".$ftp->message()."\n";$failed=1;
   $failedlog.="   Directory: $pwd\n";
   }
  $ftp->quit;
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Use the STDERR and STDOUT logging above and you've got a full and complete track of what happened in the ftp upload etc. Then you just need to email the log file and the job's done.