CiviCRM with Smarty

CiviCRM has Smarty support which enables useful logic for contribution emails and similar things, but it is not enabled for email by default. You must edit /wp-content/uploads/civicrm/civicrm.settings.php and enable Smarty:

/**
 * Enable this constant if you want to send your email
 * through the smarty templating engine (allows you to do 
 * conditional and more complex logic)
 **/
if (!defined('CIVICRM_MAIL_SMARTY')) {
  define( 'CIVICRM_MAIL_SMARTY', 1 );
}

In addition, you should disable entities in CK editor. You can do that at Administer->Customize Data & Screens->Display Preferences. Then scroll down and click the “Configure CKEditor” button.

On the subsequent page, you will need to set entities to false.