Решил задачу, может кому ещё пригодится
Скрипт для экспорта
header("Content-type: text/html; charset=utf-8");
include "standalone.php";
$objectTypes = umiObjectTypesCollection::getInstance();
$objectTypeId = $objectTypes->getBaseType("users", "user");
$sel = new umiSelection;
$sel->addObjectType($objectTypeId);
$result = umiSelectionsParser::runSelection($sel);
$objects = umiObjectsCollection::getInstance();
foreach($result as $userId) {
$object = $objects->getObject($userId);
$type=$object->getTypeId();
$users[]=$object;
}
$exporter=new xmlExporter("umiDump20");
$exporter->setShowAllFields(true);
$exporter->addObjects($users);
$result=$exporter->execute();
$result->save('./sys-temp/export/umidump.xml');
Скрипт для импорта
header("Content-type: text/html; charset=utf-8");
error_reporting(E_ALL);
include "standalone.php";
$dir = CURRENT_WORKING_DIR . "/export";
$importer = new xmlImporter();
$importer->loadXmlFile($dir . "/umidump.xml");
$importer->setUpdateIgnoreMode(false);
$importer->setFilesSource($dir);
$importer->execute();