Is there any code available which will allow one to change the default base map used within the Story Map app?
Just to check. You want to add a control into a story map so that your end users can change the basemap right?
For now it will be fine just to be able to replace the existing ArcGIS online base map with our own base map. I have done this and published the web application via our ArcGIS portal, but the configuration is still referencing lots of Java script files from on the ESRI site. Is it possible to change the config of the story map?
In the web map or web maps you are displaying in the Story Map, just change the basemap directly in ArcGIS Online, assuming you are the owner of the map. The Story Map app code doesn't control which basemap the map(s) are using. The Story Map app just displays the map(s) using whatever basemap the map author gave it in ArcGIS Online. So go here in ArcGIS Online and either make a new web map or load in an existing one: http://www.arcgis.com/home/webmap/viewer.html
You can then change the basemap there,
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