Path to custom map file

Hi,

I am using the Perch map field for a Google map. Everything works great, so now I am learning how to customize the map looks.

But wat is the root when linking to the custom map file? This path in Perch config.php is not working for me (I have created the folder maps in plugins, under addons in the Perch folder):

define('PERCH_MAP_JS', '/addons/plugins/maps/public_maps_custom.js');