There are 4 layers that you can modify with each button. These layers allow you to quickly change the look of any part of your button. These layers are, from top to bottom are:
Text - Captions that will appear on your button.
Cap - This layer is the top graphic for your button.
Inset - This layer sits between the cap and base.
Base - The bottom of your button.
Each layer can be modified to give your button amazing effects. Modifying transparency, color gradients, shadows, glass and beveling can net you some really outstanding results!