Yes.
Here is an example taken right from the Scripting Index for "<< Add Graphics Script". It uses the Bivariate platform, but << Add Graphics Script is also supported for the Graph Builder
Names Default To Here( 1 );
Open( "$SAMPLE_DATA/Big Class.jmp" );
biv = Bivariate( Y( :weight ), X( :height ), FitLine );
rbiv = biv << report;
framebox = rbiv[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] );
);
Jim