I switched to Magazine mode since automatically marking stories as read was not working for me and I was still having issues marking a story as read/unread in full mode.
With the preference “Mark stories as read when scrolled past” you get into a state where you cannot make a story as unread.
I think I had “Mark stories as read when scrolled past”. I want to have certain articles I want to leave as unread but when I scroll past them they are marked as read. I would then hit the K key to go backwards and mark is as unread again manually and hit the J key to move to the next story then the same story would be marked as read again.
Maybe some logic needs to be added so when you mark something as unread and then you go to the next article the article you just marked as unread is not automatically marked as read again.
Unfortunately I am finding how Newsblur works in relation to marking stories as unread/read very counter intuitive.