To edit any of the information in the structured metadata block, do not use the edit button on the right margin, as you would do for all the other sections, but rather the edit button directly attached to the metadata block on its lower left. The difference between the two is that with the left one you get a form similar to the one used for entering the metadata in the first place, while the right edit button lets you edit the DokuWiki syntax for this metadata block.
Todo
Replace screenshots of templates with actual overview pages with content.