Custom signup form assign customer to customer group

Question

I made a copy of the default Magento ce 1.9.1 customer signup form. I then added the below fields to the form

  <input type="hidden" name="group_id" value="3">
  <input type="hidden" name="success_url" value="./vipsuccess"> 
  <input type="hidden" name="error_url" value="" />

Then I copied the AccountController.php from the core/mage/customer/controllers/ to local/mage/customer/controllers I then added the below code to the public function createPostAction() section. However my issue is that when I use the form to create an account the customer is still assigned to the general group?

   public function createPostAction()
{
    $errUrl = $this->_getUrl('*/*/create', array('_secure' => true));

    if (!$this->_validateFormKey()) {
        $this->_redirectError($errUrl);
        return;
    }

    /** @var $session Mage_Customer_Model_Session */
    $session = $this->_getSession();
    if ($session->isLoggedIn()) {
        $this->_redirect('*/*/');
        return;
    }

    if (!$this->getRequest()->isPost()) {
        $this->_redirectError($errUrl);
        return;
    }

    $customer = $this->_getCustomer();
/** * Get Customer ID from customer registration form or if its not set in form post then use default. */ 
    if($this->getRequest()->getPost('group_id'))
     { 
         $customer->setGroupId($this->getRequest()->getPost('group_id')); 
     } 
     else 
     { 
         $customer->getGroupId(); 
     } 

    try {
        $errors = $this->_getCustomerErrors($customer);

    if (empty($errors)) {
            $customer->cleanPasswordsValidationData();
            $customer->save();
            $customer->setGroupId($this->getRequest()->getPost('group_id')); 
            $customer->save();
            $this->_dispatchRegisterSuccess($customer);
            $this->_successProcessRegistration($customer);
            return;
        } else {
            $this->_addSessionError($errors);
        }
    } catch (Mage_Core_Exception $e) {
        $session->setCustomerFormData($this->getRequest()->getPost());
        if ($e->getCode() === Mage_Customer_Model_Customer::EXCEPTION_EMAIL_EXISTS) {
            $url = $this->_getUrl('customer/account/forgotpassword');
            $message = $this->__('There is already an account with this email address. If you are sure that it is your email address, <a href="%s">click here</a> to get your password and access your account.', $url);
        } else {
            $message = $this->_escapeHtml($e->getMessage());
        }
        $session->addError($message);
    } catch (Exception $e) {
        $session->setCustomerFormData($this->getRequest()->getPost());
        $session->addException($e, $this->__('Cannot save the customer.'));
    }

    $this->_redirectError($errUrl);
}

Answer 1

After save updating the customer group you need to add website id too

$customer->save();        
$custid=$customer->getId();
$customeragain = Mage::getModel("customer/customer")->load($custid);
$website_id = Mage::app()->getWebsite()->getId();   
$customeragain->setData('group_id', $this->getRequest()->getPost('group_id'));
$customeragain->setWebsiteId($website_id); 
$customeragain->save();  

Answer 2

You need to also check the "Disable automatic group assignment" cause he will be reassigned after saving on VAT Validation.

If $customer is an instance of Mage_Customer_Model_Customer you can then set the field before saving with:

$customer->setDisableAutoGroupChange(1)