Form submit handler not working
In order to add another submit handler you have to add something to hook_form_alter(): check for your particular form ID, and then add a submit handler in one of the following ways:

OPTION 1:

To add a submit handler that is called as the next callback after processing the default submit handler callback you can use this:

function mymodule_form_alter(&amp;$form, &amp;$form_state) {
  if ($form_id == 'form-id-of-your-form') {
    $form['actions']['submit']['#submit'][] = 'mymodule_whatever_function';
  }
}


OPTION 2:

If OPTION 1 is not working for you, replace the third line with this:

form['#submit'][1] = 'mymodule_whatever_function';


This will add a second submit handler, or replace the second one with yours if there is already more than one.

OPTION 3:

To remove the default submit handler completely (so that "nothing will happen" on submit, or so that you can replace it with your own), use code like this:

function mymodule_form_alter(&amp;$form, &amp;$form_state) {
  if ($form_id == 'form-id-of-your-form') {
    unset($form["actions"]['submit']);
  }
}