• Activate/Deactivate Events:  Activate or deactivate the events.
• Number of Events per page: Set how many events per page you want to display on the Events: List and Events: Past page templates.
• Excerpt limit: Set the length of the excerpt displayed for every event on the Events: List and Events: Past page templates.
• Custom Post Type name, singular: Write the name at singular.
• Custom Post Type name, plural: Write the name at plural.
• URL Rewrite: The text displayed in the URL when you view a single event page. For example, set this to event for your URLs to look like site.com/event/event-name.

After changing this field go to Settings → Permalinks → Save Changes.