Cant RSVP for Events since upgrade to V1.7.4

I upgraded Events to version V1.7.4 today. Since then I have two issues. The first issue is that users are unable to RSVP to any event, old or new. A message comes up that the event capacity has been reached. The other issue is that once an event is created, it cannot be modified. The Update button is greyed out and will not activate no matter what change I make to the event.