I've spotted a bug in this module...You get an error when using special characters such as quote ' in the comment or name of a wish list.

To fix, in file includes/classes/wishlist_class.php, where ever there the name or comment is written or updated, I've changed the code to use prepare_input

$this->_oDB->prepare_input(xxx)

Where 'xxx' is the field being written, i.e. $name, $comment, $aArgs['name'], $aArgs['comment']