The General Settings page is used to for settings that are used in multiple places in Mooberry Book Manager.
Show Placeholder Cover On
Mooberry Book Manager uses a placeholder cover in places where a book does not have a book cover set. This option lets you turn the placeholder image on or off for Book Pages and Widgets.
Placeholder Cover Image
This is where you can set the actual image used for the placeholder cover. Mooberry Book Manager comes pre-installed with a default placeholder cover.