Featured image add-on

This is the item from the feed I'm currently experimenting with:

<author>Martina Shabonet</author>
<description>#Uppdrag1 #thisisorebro</description>
<pubDate>Thu, 10 Jan 2013 13:02:22 GMT</pubDate>

Everything except the image seems to work, I've enabled the "featured image" add-on but it doesn't download the image in <url> nor does it set it as the featured image.

This is the reason I got autoblogged - what can I do to make it work as intended?

Best regards,