Google Maps Error in WordPress Customizer

I am using X Theme, by THEMECO. When I activate WPMUDEV Google Maps, the Appearance Customizer Loading Icon spins endlessly.

It appears to be generating the following error:

Uncaught ReferenceError: _agm is not defined

This is coming from line 4 of loader.min.js, which reads "function agmInitialize(){return window._agmMapIsLoaded=!0,void 0!==window.google.maps.Map._agm_get_markers?!0:slight_frown:window.google.maps.Map.prototype._agm_markers=[],window.google.maps.Map.prototype._agm_get_markers=function(){return this._agm_markers},window.google.maps.Map.prototype._agm_clear_markers=function(){this._agm_markers=[]},window.google.maps.Map.prototype._agm_add_marker=function(t){this._agm_markers.push(t)},window.google.maps.Map.prototype._agm_remove_marker=function(t){this._agm_markers.splice(t,1)},void 0)}function loadGoogleMaps(){if("object"==typeof window.google&&"object"==typeof window.google.maps)return agmInitialize();var t="",e="",i=document.createElement("script"),a=_agm.libraries.join(",");try{t=document.location.protocol}catch(n){t="http:"}if(void 0!==window._agmLanguage)try{e="&language="+window._agmLanguage}catch(n){e=""}i.type="text/javascript",i.src=t+"//maps.google.com/maps/api/js?v=3&libraries="+a+"&sensor=false"+e+"&callback=agmInitialize",document.body.appendChild(i)}window._agmMapIsLoaded=!1,jQuery(window).load(loadGoogleMaps);"