With this plugin, you can enter your custom options datas. It is very easy to install and use. Even if you do not have expertise in PHP.
Value field from varchar(255) to text
Correcting following suggestion by Andy Stratton in http://wordpress.org/support/topic/plugin-custom-options-plus-stripslashes-needed-on-submission-of-content?replies=1
New Layout using WP List Table
New item button and UTF8 fixed bug
Tested up to WordPress 3.8.1