Vt *: In import, vtiger.batchevent.save is triggered, but then in EventTrigger class it restricts events to only 3 classes. This does not allows to execute custom registered function for batch event.

In include/events/VTEventTrigger.inc at line 82:

if(CRMEntity::isBulkSaveMode()) { query .= " AND handler_class IN (" . generateQuestionMarks(self::mandatoryEventClass) . ")"; array_push(params, self::mandatoryEventClass); }

and

private static $mandatoryEventClass = array('VTEntityDelta', 'ModTrackerHandler', 'PBXManagerBatchHandler');

As such all the batch events are restricted to be handled by only the mentioned classes.