Currently (as far as I can tell), it's only possible to add a custom sort order to articles on the main blog page. When you're on an individual item's page and have created Prev/Next links, these always use the previous or next item, sorted by 'Created date'. I would like the Prev/Next links to also conform to the custom sort order.

The most straightforward way to achieve this would be, to me, to be able to designate a field as the default sort field for that CMS collection.