User registration form at a new menu path got error after submit

Question

I'm creating an employee directory. I created a menu path which renders user registration form with profile fields. When I submit the form, I got some unknown errors. I did fill out every fields in the form, but drupal shows "required" errors.

Error
The website encountered an unexpected error. Please try again later.

• Password field is required.
• You must enter a username.
• You must enter an e-mail address.
• Notice: Undefined index: array_parents in field_default_form_errors() (line 369 of D:\fakepath\testsite\modules\field\field.form.inc).
• Recoverable fatal error: Argument 2 passed to drupal_array_get_nested_value() must be an array, null given, called in D:\fakepath\testsite\modules\field\field.form.inc on line 369 and defined in drupal_array_get_nested_value() (line 6490 of D:\fakepath\testsite\includes\common.inc).

I have hook_form_alter in which some fields are made hidden. Here is my code snippet in my custom module.

<?php
/*
 * Implementation of hook_menu()
 */
function mymodule_menu(){
    $items['employee/create'] = array(
        'title' => t('Create Directory'),
        'page callback' => 'drupal_get_form',
        'access callback' => 'mymodule_access_directory',
        'page arguments' => array('mymodule_employee_create_form'),
        'type' => MENU_NORMAL_ITEM,
        'weight' => 0,
    );
    return $items;
}
/*
 * Implementation of access callback for the menu
 */
function mymodule_access_directory(){
    global $user;
    # administrator can only access this
    if( in_array('administrator', $user->roles) ){ 
        return TRUE;
    }
    return FALSE;
}
/**
 * Home page which shows latest entered ten legs with cheapest tickets
 */
function mymodule_employee_create_form(){
    drupal_set_title('Create Employee Directory');
    return drupal_get_form('user_register_form');
}

/**
 * Implementation of hook_form_alter
 * Override form structure
*/
function mymodule_form_alter(&$form, &$form_state, $form_id) {

    if($form_id == 'user_register_form'){       
        if($_GET['q'] == 'employee/create'){ # admin only can access this page
            # hide drupal default role selection; default role is employee
            $form['account']['roles']['#default_value'] = array(6);
            _mymodule_hide_elem($form, 'roles', 'account');
            # hide auto assign role selection; default role is employee
            $form['autoassignrole_user']['user_roles']['#default_value'] = 6;
            _mymodule_hide_elem($form, 'autoassignrole_user');
            # hide Status
            _mymodule_hide_elem($form, 'status', 'account');
            # hide Notify
            _mymodule_hide_elem($form, 'notify', 'account');

            # Change "Create new account" to "Create"
            $form['actions']['submit']['#value'] = 'Create';
        }


    }
}   

function _mymodule_hide_elem(&$form, $name, $group=NULL){
    if($group){
        $form[$group][$name]['#prefix']     = '<div style="display:none">';
        $form[$group][$name]['#suffix']     = '</div>'; 
        $form[$group][$name]['#required']   = FALSE;        
    }else{
        $form[$name]['#prefix']     = '<div style="display:none">';
        $form[$name]['#suffix']     = '</div>'; 
        $form[$name]['#required']   = FALSE;
    }
}
?>

Answer 1

My mistake in my hook_menu(). The page arguments should be array('user_registration_form') and I removed the custom page callback mymodule_employee_create_form(). It did work as expected.

function mymodule_menu(){
    $items['employee/create'] = array(
        'title' => t('Create Directory'),
        'page callback' => 'drupal_get_form',
        'page arguments' => array('user_register_form'),        
        'access callback' => 'mymodule_access_directory',
        'type' => MENU_NORMAL_ITEM,
        'weight' => 0,
    );
    return $items;
}