twMAddSpot( aStruct, nHndl )
 ----------------------------------------------------------------------------
     Add a spot to the TSDWIN internal region array. You may store
     anything you wish with this function. If you are using TSDWIN MAXI
     functions, you will not need to use twMAddSpot().

       Arguments:

     aStruct - 'A' Array to define the structure of the hot spot. It
                   should minimally consist of the coordinates and a
                   code block for execution to be useful.

       Return:

     Handle of the spot for later release with twMDelSpot()

       Example:

     nHandle := twMAddSpot( 5, 5, 6, 7, {|| Help() })