- Set maxComponents=1 for an area such as promos.
- Use the Add component action in the action bar to add components.
- When you reach the max limit, keep adding components. They are not rendered on the page but you can find them in JCR.
- Area should not allow adding components beyond the limit.
- Action bar command Add component should be disabled when the limit is reached.
Reported by Hans-Peter Meister in documentation comment http://documentation.magnolia-cms.com/display/DOCS/Areas?focusedCommentId=82123052#comment-82123052