Mark Event as Completed

It is currently not possible to set a normal event as completed.
However you can try the following workaround:

  1. In Week Calendar go to Settings > Auto color / Auto icon (which ever you prefer)
  2. Create a new rule "When Notes contains text Completed"  use icon / color
  3. In Week Calendar go to Settings > General > Action menu > Add menu item > Set notes 
  4. Go back to the menu list and tap set notes
  5. Add "Completed" text in the box and give it a title.
  6. Select an event, then tap the Tools button at the bottom
  7. Select "Set notes" action and select "Completed" text. This should then trigger the auto icon / color rule.