OK there are a couple of things I overlooked.
First is that the first [0] should not be updated... since that is referring to the form element and not the address.
Second, it appears you are mapping the first point three times. Maybe it is repeated in a recordset or something, but for some reason it is appearing three times in the code. Since that is the case the second button should use this onClick code:
addDirections(this.form.elements[0].value, wagmp_map_1_obj.addresses[3].full,true,wagmp_map_1_obj.obj,wagmp_map_1_obj.icons[3],wagmp_map_1_obj.points[3]);