Initially, we had version 2.5.3, then updated to version 2.5.5, which did not produce any results. After the release of version 2.5.6 it was updated without uninstalling the previous version, but it was not helpful. The result you can see here - stkatharinedrexel.org/component/content/article/44/23-building-progress

Errors in the log file
Notice: Trying to get property of non-object in / home / stkatharinedrexel / www / plugins / content / jw_sigpro.php on line 247

May be any special settings in the flickr account required or anything else?

Thank you,
Ed

Did you use an API key for your images?

Thank you Katia!
This new requirement with Flickr was overlooked on our part.  Thanks for pointing this out.
Have a great day, Ed

documentation
www.joomlaworks.net/content/view/51/41/

Flickr Integration: Since October 2011, Flickr changed some of its API requirements and now an API key is required in order for you to be able to embed Flickr photo sets on your site. The process to get an API key is very simple: Sign in to your Flickr account, then visit www.flickr.com/services/apps/create/ and choose to get a non-commercial key. Name your app as your website. You can safely use this API key on more than one websites, even on different domains.