When you launch a platform with JSL, the platform looks to see if it is in another display box.  If not, it creates a window for itself.  If it is in a display box, the platform just anchors itself to the parent box, which may, or may not, be in a window.
Distribution(
  Continuous Distribution( Column( :weight ) ),
  Nominal Distribution( Column( :age ) )
);
opens a new window to hold the distributions.
But
x = V List Box( 
  Distribution( 
    Continuous Distribution( Column( :weight ) ), 
    Nominal Distribution( Column( :age ) ) 
) );
just returns a display box to the variable x without opening a window.  To see it,
New Window( "My Window", x )
Above, the VListBox could hold several platforms, stacked vertically, and you can add HListBox to hold several VListBoxes and make a bunch of columns, etc.
					
				
			
			
				
	Craige