Add elements to bizodo select boxes programatically

gistfile1.js

var options_to_add = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,"20+"];


var event = document.createEvent("MouseEvents");
event.initMouseEvent("click", true, true, window,
    0, 0, 0, 0, 0, false, false, false, false, 0, null);

for(var i=0,len=options_to_add.length;i<len;i++){
        $$(".option_add")[0].dispatchEvent(event)
        var empty_element = $$(".option_editor_row").filter(function(el){return el.firstChild.value == ""})[0];
        empty_element.firstChild.value = options_to_add[i];
}