twShadow( wT, wL, wB, wR, wSType )
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     Displays a shadow for the region defined by relative screen
     coordinates wT,wL,wB,wR in the position specified.

       Arguments:

     wT,wL
     wB,wR   - 'N' Relative Window Coordinates. This defaults to
                   display area for the current window if not passed.

     Position     - 'N' Shadow type using the 1,3,7,9 keys on the
                        numeric keypad. Defaults to none.

       Return:

     Current window handle.

       Example:

     twShadow( 3, 7, 9, 27, 7 )

     Shadows region defined by relative screen coordinates 3,7,9,27
     with a shadow originating at the upper left corner of the region.