The last post in this topic fixes the problem!
You must replace line 26 with:
$this->method_description = __( 'Increase your social media exposure by 10 percent! ShareYourCart helps you get more customers by motivating satisfied customers to talk with their friends about your products. For help with ShareYourCart view the <a href="http://www.woothemes.com/woocommerce-docs/user-guide/shareyourcart/">documentation</a>.', 'woocommerce' );