I've submitted an update to this plugin (v1.1.0) to add support for Zen Cart v1.5.1 (the config.core.php has changed) and remove support for (obsolete) v1.3.8a.
I've submitted an update to this plugin (v1.1.0) to add support for Zen Cart v1.5.1 (the config.core.php has changed) and remove support for (obsolete) v1.3.8a.