How to Set Full Page Background Image
To set a full page background image, go to OptimizePress 3 Builder and click on 'Settings' located on the upper-left corner of the screen.
Click 'Page Background' to show the 'Background Image' option then click on 'Set Image' button.
Select the image you want to set as full page background then click 'Insert into page' button.
Once you add your background image, you may choose the background settings like this: