Some sections in the kit use the Google Maps API. In order to be able to display maps in your page, you will need to add your API Key to the link that imports the library from Google.
Here are the steps you need to take:
Scroll to the “Get an API key” Title and press “Get a Key” Button
Choose a name for your project then press on Create and Enable API
Get the Key and place it in your project where is this script: