Your theme must support the core WordPress implementation of Custom Backgrounds theme feature..
Your layout must be boxed somehow or opacity should be added to the page content container for the background slideshow to be seen ..
There is settings page, and you will find meta box on edit screens for posts, pages and products...
Within the meta box, you can select slideshow and enable or disable it for that particular post or page...
Unfortunately, there's just no reliable way for the plugin to overwrite the background if the theme doesn't support this feature..
Just to make sure, check with your author and make sure that they support the WordPress custom-background theme feature..
Your theme must support Custom Backgrounds feature for this plugin to work..
Browse the code, check out SVN repository, or subscribe to the development log by RSS...
Major bug fixes, like propper animations, transitions, and timings -> If you update from version, you will have to save each slideshow you created and the missing options will then be available...
Extended and corrected the documentation and the documentation of the code..
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