Error:  Data structure returned is not convertible in the requested format. Try to call this method with the parameters '&format=original&serialize=1'; you will get the original php data structure serialized. The data structure looks like this: 
 $data = array (
  0 => 
  array (
    'uniqueId' => 'General_Actions',
    'name' => 'Behaviour',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => 'customdimension2',
        'name' => 'Page Author',
      ),
      1 => 
      array (
        'uniqueId' => 'customdimension4',
        'name' => 'Page Location',
      ),
      2 => 
      array (
        'uniqueId' => 'customdimension5',
        'name' => 'Page Type',
      ),
      3 => 
      array (
        'uniqueId' => 'VisitorInterest_Engagement',
        'name' => 'Engagement',
      ),
      4 => 
      array (
        'uniqueId' => 'Transitions_Transitions',
        'name' => 'Transitions',
      ),
      5 => 
      array (
        'uniqueId' => 'General_Downloads',
        'name' => 'Downloads',
      ),
      6 => 
      array (
        'uniqueId' => 'Actions_SubmenuPagesEntry',
        'name' => 'Entry pages',
      ),
      7 => 
      array (
        'uniqueId' => 'Actions_SubmenuPagesExit',
        'name' => 'Exit pages',
      ),
      8 => 
      array (
        'uniqueId' => 'General_Outlinks',
        'name' => 'Outlinks',
      ),
      9 => 
      array (
        'uniqueId' => 'Actions_SubmenuPageTitles',
        'name' => 'Page titles',
      ),
      10 => 
      array (
        'uniqueId' => 'General_Pages',
        'name' => 'Pages',
      ),
      11 => 
      array (
        'uniqueId' => 'Actions_SubmenuSitesearch',
        'name' => 'Site Search',
      ),
      12 => 
      array (
        'uniqueId' => 'Events_Events',
        'name' => 'Events',
      ),
      13 => 
      array (
        'uniqueId' => 'Contents_Contents',
        'name' => 'Contents',
      ),
      14 => 
      array (
        'uniqueId' => 'PagePerformance_Performance',
        'name' => 'Performance',
      ),
      15 => 
      array (
        'uniqueId' => 'UsersFlow_TopPaths',
        'name' => 'Top Paths',
      ),
      16 => 
      array (
        'uniqueId' => 'UsersFlow_UsersFlow',
        'name' => 'Users Flow',
      ),
      17 => 
      array (
        'uniqueId' => 'SearchEngineKeywordsPerformance_CrawlingErrors',
        'name' => 'Crawling errors',
      ),
    ),
  ),
  1 => 
  array (
    'uniqueId' => 'General_Visitors',
    'name' => 'Visitors',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => 'customdimension1',
        'name' => 'User Type',
      ),
      1 => 
      array (
        'uniqueId' => 'DevicesDetection_Devices',
        'name' => 'Devices',
      ),
      2 => 
      array (
        'uniqueId' => 'DevicesDetection_Software',
        'name' => 'Software',
      ),
      3 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      4 => 
      array (
        'uniqueId' => 'UserCountry_SubmenuLocations',
        'name' => 'Locations',
      ),
      5 => 
      array (
        'uniqueId' => 'VisitTime_SubmenuTimes',
        'name' => 'Times',
      ),
      6 => 
      array (
        'uniqueId' => 'UserCountryMap_RealTimeMap',
        'name' => 'Real-time Map',
      ),
      7 => 
      array (
        'uniqueId' => 'General_RealTime',
        'name' => 'Real-time',
      ),
      8 => 
      array (
        'uniqueId' => 'Live_VisitorLog',
        'name' => 'Visits Log',
      ),
      9 => 
      array (
        'uniqueId' => 'UserId_UserReportTitle',
        'name' => 'User IDs',
      ),
      10 => 
      array (
        'uniqueId' => 'CustomVariables_CustomVariables',
        'name' => 'Custom Variables',
      ),
    ),
  ),
  2 => 
  array (
    'uniqueId' => 'Referrers_Referrers',
    'name' => 'Acquisition',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => 'Referrers_WidgetGetAll',
        'name' => 'All Channels',
      ),
      1 => 
      array (
        'uniqueId' => 'Referrers_URLCampaignBuilder',
        'name' => 'Campaign URL Builder',
      ),
      2 => 
      array (
        'uniqueId' => 'Referrers_Campaigns',
        'name' => 'Campaigns',
      ),
      3 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      4 => 
      array (
        'uniqueId' => 'Referrers_SubmenuSearchEngines',
        'name' => 'Search Engines & Keywords',
      ),
      5 => 
      array (
        'uniqueId' => 'Referrers_Socials',
        'name' => 'Social Networks',
      ),
      6 => 
      array (
        'uniqueId' => 'Referrers_SubmenuWebsitesOnly',
        'name' => 'Websites',
      ),
      7 => 
      array (
        'uniqueId' => 'SearchEngineKeywordsPerformance_CrawlingStats',
        'name' => 'Crawling overview',
      ),
    ),
  ),
  3 => 
  array (
    'uniqueId' => 'Goals_Goals',
    'name' => 'Goals',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '4',
        'name' => 'New Job Application',
      ),
      1 => 
      array (
        'uniqueId' => '5',
        'name' => 'View Submit Job',
      ),
      2 => 
      array (
        'uniqueId' => '6',
        'name' => 'New Resume',
      ),
      3 => 
      array (
        'uniqueId' => '7',
        'name' => 'Liveaboard.com click',
      ),
      4 => 
      array (
        'uniqueId' => '8',
        'name' => 'Agoda click',
      ),
      5 => 
      array (
        'uniqueId' => '9',
        'name' => 'User Comments',
      ),
      6 => 
      array (
        'uniqueId' => '10',
        'name' => 'Newsletter Signup',
      ),
      7 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      8 => 
      array (
        'uniqueId' => 'MultiChannelConversionAttribution_MultiAttribution',
        'name' => 'Multi Attribution',
      ),
    ),
  ),
  4 => 
  array (
    'uniqueId' => 'Goals_Ecommerce',
    'name' => 'Ecommerce',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => 'Goals_EcommerceLog',
        'name' => 'Ecommerce Log',
      ),
      1 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      2 => 
      array (
        'uniqueId' => 'Goals_Products',
        'name' => 'Products',
      ),
      3 => 
      array (
        'uniqueId' => 'Ecommerce_Sales',
        'name' => 'Sales',
      ),
      4 => 
      array (
        'uniqueId' => 'MultiChannelConversionAttribution_MultiAttribution',
        'name' => 'Multi Attribution',
      ),
    ),
  ),
  5 => 
  array (
    'uniqueId' => 'AbTesting_Experiments',
    'name' => 'A/B Tests',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '9',
        'name' => 'AffiliateLinkEffectiveness',
      ),
      1 => 
      array (
        'uniqueId' => '10',
        'name' => 'IDivedThereLinkMove',
      ),
      2 => 
      array (
        'uniqueId' => '11',
        'name' => 'JobsListingCallToActionChange',
      ),
      3 => 
      array (
        'uniqueId' => '12',
        'name' => 'JobPageRelevantCallToAction',
      ),
      4 => 
      array (
        'uniqueId' => '13',
        'name' => 'DivingPageTitles',
      ),
      5 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
    ),
  ),
  6 => 
  array (
    'uniqueId' => 'CustomReports_CustomReports',
    'name' => 'Custom Reports',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '2',
        'name' => 'Bali pages, breakdown new/returning',
      ),
      1 => 
      array (
        'uniqueId' => '5',
        'name' => 'Country by New/returning with a filter',
      ),
      2 => 
      array (
        'uniqueId' => '8',
        'name' => 'Evolution KPIs',
      ),
      3 => 
      array (
        'uniqueId' => '1',
        'name' => 'Pages by New/Returning visitor',
      ),
    ),
  ),
  7 => 
  array (
    'uniqueId' => 'FormAnalytics_Forms',
    'name' => 'Forms',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '2',
        'name' => 'Comment Form',
      ),
      1 => 
      array (
        'uniqueId' => '7',
        'name' => 'Apply to Job Form',
      ),
      2 => 
      array (
        'uniqueId' => '29',
        'name' => 'Add Job Form',
      ),
      3 => 
      array (
        'uniqueId' => '30',
        'name' => 'Candidate Registration Form',
      ),
      4 => 
      array (
        'uniqueId' => '31',
        'name' => 'Resume Search',
      ),
      5 => 
      array (
        'uniqueId' => '32',
        'name' => 'Build Resume Form',
      ),
      6 => 
      array (
        'uniqueId' => '40',
        'name' => 'Contact Us Form',
      ),
      7 => 
      array (
        'uniqueId' => '41',
        'name' => 'Newsletter Signup Form',
      ),
      8 => 
      array (
        'uniqueId' => '42',
        'name' => 'Checkout Form',
      ),
      9 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      10 => 
      array (
        'uniqueId' => 'FormAnalytics_TypeRealTime',
        'name' => 'Real-time',
      ),
    ),
  ),
  8 => 
  array (
    'uniqueId' => 'Funnels_Funnels',
    'name' => 'Funnels',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '2',
        'name' => 'New Resume',
      ),
      1 => 
      array (
        'uniqueId' => '3',
        'name' => 'View Submit Job',
      ),
      2 => 
      array (
        'uniqueId' => '7',
        'name' => 'New Job Application',
      ),
      3 => 
      array (
        'uniqueId' => '8',
        'name' => 'Liveaboard.com click',
      ),
      4 => 
      array (
        'uniqueId' => '99',
        'name' => 'Sales',
      ),
      5 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
    ),
  ),
  9 => 
  array (
    'uniqueId' => 'HeatmapSessionRecording_Heatmaps',
    'name' => 'Heatmaps',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '11',
        'name' => 'Homepage',
      ),
    ),
  ),
  10 => 
  array (
    'uniqueId' => 'HeatmapSessionRecording_SessionRecordings',
    'name' => 'Session Recordings',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => '13',
        'name' => 'Homepage',
      ),
    ),
  ),
  11 => 
  array (
    'uniqueId' => 'MediaAnalytics_Media',
    'name' => 'Media',
    'subcategories' => 
    array (
      0 => 
      array (
        'uniqueId' => 'MediaAnalytics_TypeAudienceLog',
        'name' => 'Audience Log',
      ),
      1 => 
      array (
        'uniqueId' => 'MediaAnalytics_TypeAudienceMap',
        'name' => 'Audience Map',
      ),
      2 => 
      array (
        'uniqueId' => 'MediaAnalytics_TypeAudio',
        'name' => 'Audio',
      ),
      3 => 
      array (
        'uniqueId' => 'General_Overview',
        'name' => 'Overview',
      ),
      4 => 
      array (
        'uniqueId' => 'MediaAnalytics_MediaPlayers',
        'name' => 'Media Players',
      ),
      5 => 
      array (
        'uniqueId' => 'MediaAnalytics_TypeRealTime',
        'name' => 'Real-time',
      ),
      6 => 
      array (
        'uniqueId' => 'MediaAnalytics_TypeVideo',
        'name' => 'Video',
      ),
    ),
  ),
);