Thanks to:
docs.dhtmlx.com/doku.php?id=dhtm … ationerror
I finally figured out why my event didn’t fire.
Now that it did fire, the “errors” array looks empty, when trying alert(errors) i get an empty alert.
dp.attachEvent("onValidatationError",function(id,errors){
//any custom code
alert(errors);
return true;
});