I think I found two bugs.
1. If I try adding an external RSS like any of these it gives an error in my error_log and wont work.
2. If I import the RSS from this sites Announcements - http://xenforo.com/community/forums/announcements/index.rss it addes the oldest post first and newest posts last, as you can see here - http://chatfreaks.net/community/forums/xf-announcements.4/