How does the Latest Form block work on the Welcome page dashboard desktop in 5.8?

Mine doesn't do anything, i.e., show latest form results -- I have one contact form built with the new form block (not "legacy forms").

When I customize the welcome page, I click on the Latest Forms block, but don't have any choice to Edit Block. If I delete it and add a new instance, again, cannot edit the block.

How does one tell it what form to report on?

Thanks for any insights...