Make sure that when you are clicking on the banner, you are selecting the drop down menu for "Banner Image." It defaults to banner color. Also, some templates do not have a banner image/color. They may all be part of the background. To check this, click on the background, go to background image, and copy the address that is in the field. Go to that address to see a full image of the background. You can save this image and photoshop in a banner if you'd like, and the sizes would all match up.