The higher your shadow's vertical and horizontal setting is the higher it will "appear" from the top of your button. If the shadow is "higher" then it wouldn't appear as crisp as it would if it were say only a pixel off of the cap. Click this to apply a blur to your shadow to give it a more realistic appearance.
Set this to the distance you want your shadow to appear horizontally from the text. Negative values pushes the shadow to the left of the text, positive values push the shadow to the right of the text.
Set this to the distance you want your shadow to appear vertically from the text. Negative values pushes the shadow to the top of the text, positive values push the shadow down below the text.