JMP has a full set of graphic primitives available to all graphical platforms. They allow you to add whatever items to a graphical display as desired. Lines, text, rectangles, polygons, colors, fill patterns, etc. are all available.
Here is the script for the above Graph Builder
Names Default To Here( 1 );
Open( "$SAMPLE_DATA/Big Class.jmp" );
gb = Graph Builder(
Size( 534, 456 ),
Show Control Panel( 0 ),
Variables( X( :height ), Y( :weight ) ),
Elements( Points( X, Y, Legend( 6 ) ), Line Of Fit( X, Y, Legend( 8 ) ) )
);
rgb = gb << report;
framebox = rgb[frame box( 1 )];
framebox << Add Graphics Script(
Transparency( 0.5 );
Fill Color( {1.0, 0.5, 0.0} );
Polygon( [60, 72, 57], [75, 120, 120] );
);
The documentation for this methodology is found in the Scripting Guide in a section titled "Scripting Graphs".
Another, but not as elegant way to do this, would be to one or more of your Overlay groups. You could have A,B,C,D and Connect. You would add to your data table, the XY points for each of your A-D groups, and Graph Builder would draw them.
Jim