I would suggest Adding ">" Buttons to the screens. At the first screen hide or disable the back button. At the final screen replace the forward button with a "Finish"-button.

Or maybe a sort of graphic slider: moving along different screens simply dragging back and forth an icon, at the bottom side of the interface. If your app is meant to be touch-screen device dedicated it would be a successful strategy.

Just in case you are still lokking for answers: You could always import your finished screens into a program such as Axure or Balsamiq where you can add links to GUI elements, which will then take you to the desired screen when clicked. I find this solution very helpful to demonstrate the click flow.