An anonymous user will be prompted to login before accessing the submission form.
So does that mean if visitors want to submit an event by clicking on the customised link http://laois2016.ie/wordpress/events/community/add……. in the main menu , they will be redirected to the Word press login/register page.
So when they register/login are they automatically redirected then to the “add an event ” page
The behavior you describe is exactly right, with one difference—they are not redirected to the built-in WordPress login/register page. They are redirected to a front-end version of the login/register form.
Then, yes, upon login they are redirected to the “Add an Event” page.