I am using ltng:require as specified in the docs to load multiple js libraries -- in the correct order of dependency. However, the scripts only load about 50% of the time. The other 50% the jsVectorMap scripts never load and the afterScriptsLoaded function never fires. Any thoughts??
 

<ltng:require styles="{!join(',','/resource/slds_2_1_3','/resource/jsVectorMapCSS')}"
                  scripts="{!join(',','/resource/jQuery','/resource/jsVectorMap','/resource/jsVectorMapUS')}" 
                  afterScriptsLoaded="{!c.setScriptLoaded}" />