That error simply means that the updater either failed at downloading or extracting the files for you. If you want to "force" the updater to download the files, simply open caches.xml and change the number in there to a previous one. That number that shows up is the current revision, so if it's "4" make it "3".
<Cache ID="fivereborn" Version="4" />
To force an update you would change it to:
<Cache ID="fivereborn" Version="3" />