User registration problem - Powers tutorial

This is the script for the user registration. Is there anything here that looks suspicious and may be blocking the email information submitted by the form to be populated in the database table? My experience with PHP is limited an not sure if this is helpful to resolving my issue. Please let me know what else would be helpful if there isn't anything obvious here.

<?php
$errors = array();
if ($_POST) {
  // run the validation script
  require_once('library.php');
  try {
     // main script goes here
     $val = new Zend_Validate_Regex('/^[a-z]+[-\'a-z ]+$/i');
     if (!$val->isValid($_POST['first_name'])) {
       $errors['first_name'] = 'Required field, no numbers';
     }
     if (!$val->isValid($_POST['surname'])) {
       $errors['surname'] = 'Required field, no numbers';
     }
     $val = new Zend_Validate();
     $length = new Zend_Validate_StringLength(6,15);
     $val->addValidator($length);
     $val->addValidator(new Zend_Validate_Alnum());
     if (!$val->isValid($_POST['username'])) {
       $errors['username'] = 'Use 6-15 letters or numbers only';
     } else {
       $sql = $dbRead->quoteInto('SELECT user_id FROM users WHERE username = ?', $_POST['username']);
      $result = $dbRead->fetchAll($sql);
       if ($result) {
          $errors['username'] = $_POST['username'] . ' is already in use';
       }
     }
     $length->setMin(8);
     $val = new Zend_Validate();
     $val->addValidator($length);
     $val->addValidator(new Zend_Validate_Alnum());
     if (!$val->isValid($_POST['password'])) {
       $errors['password'] = 'Use 8-15 letters or numbers only';
     }
     $val = new Zend_Validate_Identical($_POST['password']);
     if (!$val->isValid($_POST['conf_password'])) {
       $errors['conf_password'] = "Passwords don't match";
     }
     $val = new Zend_Validate_EmailAddress();
     if (!$val->isValid($_POST['email'])) {
       $errors['email'] = 'Use a valid email address';
     }
     if (!$errors) {
       // insert the details in the database
       $data = array('first_name'  => $_POST['first_name'],
                     'family_name' => $_POST['surname'],
                         'username'    => $_POST['username'],
                         'password'    => sha1($_POST['password']));
       $dbWrite->insert('users', $data);
        header('Location: login.php');
     }
  } catch (Exception $e) {
     echo $e->getMessage();
  }
}
Thanks for any help.