We found the problem.
Please add the code
function execute($task){
if(substr($task,0,12)=='triggerplug-'){
JPluginHelper::importPlugin( 'hikashop' );
$dispatcher =& JDispatcher::getInstance();
$parts = explode('-',$task,2);
$event = 'onTriggerPlug'.array_pop($parts);
$dispatcher->trigger( $event, array( ) );
return true;
}
return parent::execute($task);
}
before the line:
function display($cachable = false, $urlparams = false){
in the file administrator/components/com_hikashop/helpers/helper.php and that should then work.