Changing allow_url_include=1 is not safe. It's set to disabled by default.
When I include something on the local machine I always use something like this so it can be ported across platforms. Hardcoding an include below the web root can lead to mandatory rewrites if you're on a shared hosting plan or if you don't control your server. Also this is more portable for a dev/production environment.
<?php
require_once($_SERVER['DOCUMENT_ROOT'].'/opencart/admin/kzm/kzm.utils.php');
?>
If you need to get to another directory you can always do something like this:
<?php
require_once($_SERVER['DOCUMENT_ROOT'].'/../website2_folder/opencart/admin/kzm/kzm.utils.php');
?>