Hi @SEVERO,
Thank you for reaching out to us. Instead of using a third party plugin I’d recommend you to use the theme’s background feature to avoid conflicts and potential errors. You can set the background image via Theme Options > Layout and Design > Background Options
You can also set the background images on individual pages via Page Settings. Simply edit your pages in either WP Page editor or Cornerstone (see screenshot)
Please note that, we cannot provide support for third party plugins or scripts as our support policy in the sidebar states due to the fact that there is simply no way to account for all of the potential variables at play when using another developer’s plugin or script. Because of this, any questions you have regarding setup, integration, or troubleshooting any piece of functionality that is not native to X will need to be directed to the original developer.
Hope this helps!