There appears to be no Picture Widget for displaying a photo library in Mimic. Is there anyway to add this?
No way that I know of, there is no database for pictures.
It appears that previous versions of Mimic had a "Pictures" tab and most other skins for Kodi 17 support Pictures. So why not in this version?
Are you talking about widgets or menu items? Because the menu item can easily be created.
The menu item. Sorry for using the wrong term.
It's not in Mimic's default menu, but you can add it via the menu customizer.
When you select Change Action for a menu item, and then Pictures, it is empty; there is nothing there to select (no files, etc) and therefore you cannot select Pictures.