I am having the same problem, but I am just trying to do it in the arcgis.com map viewer. My gallery only shows up when I am logged in, when logged out it displays esri's gallery. Is there any way to allow the public to see my basemap gallery instead of esri's? The basemaps and their group are all shared publicly. Here is a link to my map: http://bit.ly/19AjKxx
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