Roots Better Gmaps is a Visual composer extension created to give you more flexibility when adding Google maps to your website.
This plugin is an extension for Visual Composer
When you download the plugin from codecanyon you will have a Documentation folder that contains the document you are reading just now and the plugin .zip archive.
In order to install the plugin go to Plugins -> Add New -> Upload. Click Browse and select the .zip archive file. Then click Install now. After installation is done activate the plugin.
In order to make the maps work in your website you need to set you Google Maps API KEY.
In order to do this you need to Select Settings -> Better Google Maps Settings
When adding a new map with this Visual Composer extension add the desired information as shown in the image below.