how to reproduce:
1. export single template
2. edit the xml file (change the template name)
3. import it and you'll get Fatal error: Call to undefined method CTemplate::add() in include/export.inc.php on line 585

rev 8641 include/export.inc.php, line 585 states:
$current_host = CTemplate::add($host_db);

but i believe it should be
$current_host = CTemplate::create($host_db);