Thanks a lot for the feedback. The error you quoted is indeed very interesting, shows the Archived Articles didn't import properly, but the rest did (which is nice to see). The GtkWarning message though is much less nice...
- You should see in the widget all the unread articles, it probably happens you only have 3 unread articles (I hope that's what it is).
- You don't really "read" articles in the widget, you just browse the titles, so they remain unread until you open the app. I was considering another button as a "Mark as read", but didn't really see where it'd fit.