This would be a very rare situation, its extremely uncommon for you to not get 1 share in at 512 difficulty before a block.  The issue with the 1 block earlier was more of an issue where  the shares were queued to be put in the database and the change came before  they were, it wasnt because you didnt get any shares in.  We realized the issue after we saw the payout reportt and are working on correcting it so it won't happen again, we already made some changes to prevent it and once we get another short block we can confirm that won't happen again.  So just to be clear, it was not because you didnt get any shares in, in time, you did but they just went towards the next block because of queuing on our end.