Perl Mechanize firefox Click issue

[vkknava]

I have written a code to automate my webpage to do a search and download a report. Till selection of the report everything works fine. But download click is not working after clicking checkbox. It works well if i keep the download click bust before checkbox select. But I need to select the reports to click download.

<form action="xxx.net:1234/xxx/xxx/abc.do?starttrail=true&advancedSear
+ch=true" onsubmit="javascript:deleteReport(this);">
<input type="hidden" name="formAction" id="formAction"/>
<table id="reportLog" class="content" cellspacing="0" cellpadding="0">
<tr>
    <th class="actionHeader" colspan="5">
        <div class="leftButtons">
                    <input type="button" id="deleteButton" name="delet
+e" value='Delete' height="5"  />
                    <input type="button" id="downloadButton" name="dow
+nload" value='Download' height="5" />
                </div>            
    </th>
  </tr>
<tr>
  <th class="column checkbox"><input type="checkbox" name="selectAll" 
+ onClick='javascript:checksOnlyActive(this.checked, this.form, "selec
+tedLogs")'/></th>
</tr>
<tr>
  <td class="checkboxCol ">
    <input type="checkbox" name="selectedLogs" value='178746' /></td>
  <td >Complete</td>
  <td >def</td>
  <td >123abc</td>
  <td  nowrap>
     Feb 14, 2016 1:31 PM
  </td>
</form>

here is the perl code.

#! C:/Perl64/bin/perl.exe

use strict;
use warnings;
use WWW::Mechanize::Firefox;

   my $mech = WWW::Mechanize::Firefox->new();
   my $url = 'login_path';
   my $url_2 = 'search_tab_path';

sub print_status()
{
   my $status =$mech->status();
   print "status = $status\n";
}

   $mech->get($url,
              activate  => 1,
              autoclose => 0,
              js_JSON   => 'native');
   print_status();

    my $username = 'aaa'; 
    my $password = 'bbb';

    $mech->form_name('logonForm') ;
    $mech->field ('username' => $username);
    $mech->field ('password' => $password);
    #print_status();
    $mech->click({ xpath => '//*[@value="Login"]' });
    #print_status();
    $mech->get($url_2);
    $mech->form_name("reportLogCatalogForm");
    $mech->field('searchV','vkknava');
    $mech->click({ xpath => '//*[@id="searchButton"]' });
    #$mech->click({ xpath => '//input[@onclick]',synchonize => 0 }, 1)
+;
     my $l = $mech->xpath('//input[@onclick]', single => 1);
      $mech->synchronize('DOMFrameContentLoaded', sub {
          $l->__click()
      });
$mech->click({ xpath => '//*[@id="downloadButton"]',synchonize => 0 })
+;

Somebody is expertise here?