Ha Thach,
  I don't think the original developer is maintaining this widget any more but if you really want this widget updated then these are the changes to make.
TocLayerMenu.mxml
            private function bordercontainer1_rollOverHandler(event:MouseEvent):void
            {
                AppEvent.dispatch(AppEvent.RESET_TOC_HIDE_TIMER, "true");
            }
            private function bordercontainer1_rollOutHandler(event:MouseEvent):void
            {
                AppEvent.dispatch(AppEvent.START_TOC_HIDE_TIMER, null);
            }
TransparencyMenuItem.mxml
            protected function transparencyBorderContainer_rollOverHandler(event:MouseEvent):void
            {
                AppEvent.dispatch(AppEvent.RESET_TOC_HIDE_TIMER, "true");
            }
            protected function transparencyBorderContainer_rollOutHandler(event:MouseEvent):void
            {
                AppEvent.dispatch(AppEvent.START_TOC_HIDE_TIMER, null);
            }