I have realised that once an event is marked as completed, it is still appearing in the event calendar. You have to go in and deleted manually. I would of thought that this would have gone once completed? If that is not possible, who it be ok to have a change colour to something like green at least? That way it would visually show that it was done.
At the moment all it does is strikethrough the event, but you only see that if you click into the event on the calendar (images included).