Photos: can be dragged and put in the order that you would like them to show up. The first top photo will always be the first photo people see on your Ad.
Coupon codes: can be used at the first time of listing or you can use them as a upgrade payment. Just log in and go to "My listings" page, click on where it says upgrade go to the lower right side of screen where it shows the choices for the features on top of that area you will see a "do you have a coupon code" click that link and then enter your coupon code. This will then change your Ad to whatever features the coupon code is for.
If this fails please give me a call to help you with it at: 920-242-0468