Don't have time tonight - dinner and family beckon but if you replace these two subs with the code below it works fine (you can also delete the _read_data() sub which is dead. Have not had time to test it properly yet but this seems to do the trick. BTW uploads are disabled by default so you will need to $CGI::Simple::DISABLE_UPLOADS = 0;

sub _parse_multipart {
    my $self = shift;
    my ($boundary) = $ENV{'CONTENT_TYPE'} =~ /boundary=\"?([^\";,]+)\"
+?/;
    unless ($boundary) {
        $self->cgi_error( '400 No boundary supplied for multipart/form
+-data' );
      return 0;
    }
    # BUG: IE 3.01 on the Macintosh uses just the boundary, forgetting
+ the --
    $boundary = '--'.$boundary unless $ENV{'HTTP_USER_AGENT'} =~ m/MSI
+E\s+3\.0[12];\s*Mac/i;
    $boundary = quotemeta $boundary;
    my $got_data = 0;
    my $data = '';
    my $length  = $ENV{'CONTENT_LENGTH'} || 0;
    my $CRLF = $self->crlf;

READ:

    while ( $got_data < $length ) {
      last READ unless sysread( STDIN, my $buffer, 4096 );
        $data .= $buffer;
        $got_data += length $buffer;

    BOUNDARY:

        while ( $data =~ m/^$boundary$CRLF/ ) {
          next READ unless $data =~ m/^([\040-\176$CRLF]+?$CRLF$CRLF)/
+o;    
            my $header = $1;
            (my $unfold = $1) =~ s/$CRLF\s+/ /og; 
            my ($param) = $unfold =~ m/form-data;\s+name="?([^\";]*)"?
+/;
            my ($filename) = $unfold =~ m/name="?\Q$param\E"?;\s+filen
+ame="?([^\"]*)"?/;
            if (defined $filename ) {
                my ($mime) = $unfold =~ m/Content-Type:\s+([-\w\/]+)/i
+o;
                $data =~ s/^\Q$header\E//; 
                ( $got_data, $data, my $fh, my $size ) = $self->_save_
+tmpfile( $boundary, $filename, $got_data, $data );
                $self->_add_param( $param, $filename );
                $self->{'.filehandles'}->{$filename} = $fh if $fh;
                $self->{'.tmpfiles'}->{$filename} = {'size'=>$size, 'm
+ime'=>$mime } if $size;
              next BOUNDARY;
            }
          next READ unless $data =~ s/^\Q$header\E(.*?)$CRLF(?=$bounda
+ry)//s;
            $self->_add_param( $param, $1 );
        }
    }
  return $got_data;
}

sub _save_tmpfile {
    my ( $self, $boundary, $filename, $got_data, $data ) = @_;
    my $fh;
    my $CRLF = $self->crlf;
    my $length  = $ENV{'CONTENT_LENGTH'} || 0;
    my $file_size = 0;
    if ( $self->{'.globals'}->{'DISABLE_UPLOADS'} ) {
        $self->cgi_error("405 Not Allowed - File uploads are disabled"
+);
    }
    elsif ( $filename ) {
        eval { require IO::File };
        $self->cgi_error("500 IO::File is not available $@") if $@;
        $fh = new_tmpfile IO::File;
        $self->cgi_error("500 IO::File can't create new temp_file") un
+less $fh;
    }
    # read in data until closing boundary found. buffer to catch split
+ boundary
    # we do this regardless of whether we save the file or not to read
+ the file
    # data from STDIN. if either uploads are disabled or no file has b
+een sent
    # $fh will be undef so only do file stuff if $fh is true using $fh
+ && syntax
    $fh && binmode $fh;
    while ( $got_data < $length ) {

        my $buffer = $data;
      last unless sysread( STDIN, $data, 4096 );

        # fixed hanging bug if browser terminates upload part way thro
+ugh
        # thanks to Brandon Black
        unless ( $data ) {
            $self->cgi_error('400 Malformed multipart, no terminating 
+boundary');
            undef $fh;
          return $got_data;
        }

        $got_data += length $data;
        if ( "$buffer$data" =~ m/$boundary/ ) {
             $data = $buffer.$data;
           last;
        }

        # we do not have partial boundary so print to file if valid $f
+h
        $fh && print $fh $buffer;
        $file_size += length $buffer;
    }
    $data =~ s/^(.*?)$CRLF(?=$boundary)//s;
    $fh && print $fh $1;   # print remainder of file if valid $fh
    $file_size += length $1;
  return $got_data, $data, $fh, $file_size;
}
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