Ran into this too with a sequence that was shared, for a few days could not get a fseq to render at all, deleted the old one, still would not render. I made some changes to the sequence last night to add a new element and it started rendering again. It went through the motions, but no file was created, not sure what to make of it as it tossed no errors either.
But have also see that Date instead of Date Modified in the details listing.
Alan