If you need a background image to span across the entire Front Cover, you can first select the background image using the mouse, and then drag/size the image to the left edge. You can manually move or size the image anywhere on the label by dragging it with the mouse, or using the sizing rectangles around the edge of the selected image.
If you need a separate background image on the left side of the Front Cover, you can drag a background image from the "Image Toolbar" using your mouse, and place it on the left side of the cover. Next click the "Set as Background" button.
Please note: Clicking the "Set as Background" button more than once will render different layouts for the background image.