Go into your Control Panel, such as cPanel, that came with your website and find phpMyAdmin so that you can see your database ...
Make sure the database that you are looking at matches the one listed in your files:
/includes/configure.php
/admin/includes/configure.php
then browse the configuration table ...
If you click on the field name, when browsing the table, configuration_id it will sort in order by how the configuration records were added ...
You might be able to see what rows you have that were "new" or part of an "add on" and not part of the original Zen Cart ...
You can also sort on the configuration_key and browse through the pages for duplicates ... where the "higher value" configuration_id is usually the last one added to the configuration table ...