Not sure how it's with JEM 2.x but noticed with JEM 3.0.7 that there is a problem with loading Google map. It needs an Api-key. Guess the problem is with JEM 2.x too? Am currently not running JEM2.x so not sure, just wanted to point out that there seems to be a problem.
Google Maps Platform rejected your request. You must use an API key to authenticate each request to Google Maps Platform APIs. For additional information, please refer to g.co/dev/maps-no-account
JEM2.x is the active development path, JEM3.x is not supported (obsolete)