I followed the tutorial you created, but while the featured image works perfectly, the gallery even following the explanations to the letter, still does not work.
Hi – External Images does not provide its own HTML gallery – it relies on whatever gallery your theme provides.
Developers of these themes often copy code from the web and/or each other, so it’s very often that themes will provide multiple display options for your gallery.
If you cycle through the gallery options, there is normally one that is coded properly that will work.
In addition, there was a new update released half an hour ago which fixes some issues with some themes. If you can download version 2.71 and test that, also try cycling through the gallery display options in your theme.
If this still does not work, please let me know which theme you are using.
Finally, if you come chat on our Discord server I can answer questions and provide help more quickly.