Thank you for getting in touch with us.
I wouldn’t recommend manually creating your own XML file as our plugin will automatically generate one based off of the marker data available in the database. Depending on the ‘Pull Method’ selected in the settings page, the plugin will then serve the map data over the respective data source.
I’d recommend importing your markers via CSV into the plugin as this will allow you to also edit/delete markers in the plugin rather than having to edit files.
I hope this helps?