Create a different screen for each break (copy your existing break screen), use a different background image for each one. Then you'll have to create a Screen Set for each one, with just that break screen in the Screen Set. For example, say you have 3 different break screens, and you want to use them for the 1st, 2nd, and 3rd breaks, respectively. Create a Screen Set called "break 1", add the "break 1" screen to it and no other screen, and for the Conditions for that Screen Set, select "Break" and enter "1" in the break number input. Move this Screen Set to the top of the list of Screen Sets. Repeat for breaks 2 and 3.