change the posterboard layout from 4 column to 3 column

Is it possible to change the posterboard layout from 4 column to 3 column .. I have been over every setting.

Also the breadcrumbs on the individual events, go to a page called events which needs some styling added to it but I cant find the page events as it doesn’t exist so is there a way to stop the breadcrumbs from going to this page.

Thanks ??

The page I need help with: [log in to see the link]