Though, I'm giving 4 stars because the idea is very good and I believe that this extension is working in older Joomla versions (that I've not tested).
It appears that you're correct about the generator tag in the atom feeds, but the plugin is working perfectly in RSS and HTML output on my test system running 2.5.4. You should have contacted me to report a bug instead of doing it here in the JED.
It's a very good extension with many social networks and easy to use but I had a problem. Before I use an extension on my server I do all the testings locally. Testing loginradius on localhost resulted in error messages. I couldn't test it locally and do any CSS changes.
So, I contacted the support team asking for a solution. And guess what?
Next day there was a solution in my inbox and an update was published!!!
Great extension and an excellent support team that you can't find even in paid extensions.
Continue this excellent work!