I think I understand now what you want.
You can add a box below, and there insert the extension you want text etc.
And of course connect to the data set, and check the box and then add code on the extension button like this:
exportfunction Button1_click(event,$item){
if( $item("#box1").collapsed ) {
$item("#box1").expand();
$item("#Button1").label = "-"
}else {
$item("#box1").collapse();
$item("#Button1").label = "+"
}
}