--- panels_tabs.module
+++ panels_tabs.module
@@ -35,12 +35,27 @@ function panels_tabs_ctools_plugin_api($module, $api) {
 function panels_tabs_panels_pre_render($display, $renderer) {
   // Don't run if we are using legacy mode
   if (panels_tabs_style_version() == 2) {
-    $renderer->prepare();
-    foreach ($renderer->prepared['regions'] as $id => $region) {
-      if ($region['style']['name'] == 'tabs') {
-        foreach ($region['pids'] as $pid) {
-          $renderer->prepared['panes'][$pid]->region_style = 'tabs';
-        }
+
+    $tabs_regions = array();
+    
+    // Check if the tabs style has been applied to entire panel
+    $global_style = $renderer->display->panel_settings['style'] == 'tabs';
+    
+    // Find out which regions are using the tabs style and add to an array
+    foreach ($renderer->plugins['layout']['panels'] as $region_id => $title) {
+      $settings = $renderer->display->panel_settings[$region_id];
+      if ($global_style && empty($settings['style'])) {
+        $tabs_regions[] = $region_id;
+      }
+      elseif ($settings['style'] == 'tabs') {
+        $tabs_regions[] = $region_id;
+      }
+    }
+    
+    // Go through all the panes and mark those that are in a tab region.
+    foreach ($renderer->display->content as $pane_id => $pane) {
+      if (in_array($pane->panel, $tabs_regions)) {
+        $renderer->display->content[$pane_id]->region_style = 'tabs';
       }
     }
   }