There seems to be a problem parsing the RSS feed from http://updates.wp.applian.com/. On that site the RSS feed link is supposedly http://updates.wp.applian.com/feed/. You can see it under the URL link on the page titled “Entries RSS”.
If the problem is with their RSS XML vs Newsblur, let me know and I can inform them. I should state that the Chrome browser does seem to want to integrate the RSS link