You have an issue, where you only changing value of hidden input, but not fires event about that change. You should know, that every js-invoked change of input field should be followed by triggering events.
Right now you trigger event only for <div> element, which is wrong, because you don't support this mechanics: $('form input').change(function(){}), where user didn't even know "is this form using your plugin, or it is bootstrap itself".
You have an issue, where you only changing value of hidden input, but not fires event about that change. You should know, that every js-invoked change of input field should be followed by triggering events.
Right now you trigger event only for
<div>element, which is wrong, because you don't support this mechanics:$('form input').change(function(){}), where user didn't even know "is this form using your plugin, or it is bootstrap itself".