Google no longer allows the use of its maps API unless you obtain a key. Pages on domains that used the Google Maps API before June 22, 2016, will continue to work (though it's not known for how long), but a page that's on a domain that didn't formerly use the API will not work properly without a key. A key may be obtained without any cost. Visit the Google developer page and click the Get a Key button. You will have to create a Google account if you don't already have one (also free). Follow the prompts to create a project (you can just accept the default name) and to create a Browser API key. Each of these steps will take some time, so don't get impatient and start clicking things repeatedly.
You may restrict use of the key to just your domain by going to the Google API Manager / Credentials section, and editing the entry for your key. But if you do so, local preview of your album will fail, because the map request will be coming from your PC, rather than from your domain. Restricting use of the key is probably an excess of caution. In theory, someone else could get your key and use it on his or her own site. This would become a problem only if the key were used for more than 25,000 map views per day, a stunningly high number. And even if that happened, it's a simple matter to delete that key, get a new one from Google, and plug it into your album(s).
If you do opt to restrict the use of your key, be very careful about how you enter the domain name. To cover all bases, enter your domain as, for example, *.example.com/* and as example.com/*, each on a separate line. Then wait at least 15 minutes before testing your page - the setting may not take effect immediately. Then, you should build and preview your album without entering your API key. When you have everything the way you want it, enter the API key, click Make Album one more time, then upload the album.
Edited by: jGromit on 28-Jun-2017 18:09 to update skin list