There is probably no need to attempt a reinstall.

The first thing to try is to clear out the folder the rss reader uses for storage:

~/.osso_rss_feed_reader

First, take a copy of feedlist.opml from this folder, as it contains your rss feeds. Then delete everything else in it. Then put feedlist.ompl back and

killall osso_rss_feed_reader

Start the RSS reader again and see how you go...