String Overrides is not overriding the "Read more" string
Might need some tweaking, but you can change the text in hook_preprocess_node(). If you set it to "Read more" you can override it with stringoverrides after, or change it to what you want at once.

In your themes template.php, add:


/**
 * Implements hook_preprocess_node().
 */
function MYTHEME_process_node(&$vars) {
  // Change default text of the read more link.
  if (isset($vars['links']['node']['#links']['node-readmore'])) {
    $vars['links']['node']['#links']['node-readmore']['title'] = t('Read more');
  }
}



Related modules:
http://drupal.org/project/readmorecontrol
http://drupal.org/project/read_more
http://drupal.org/project/linkoutreadmore