The Training Calendar that Joe from Zen Optimise was using was based on the eCommerce plugin Cart66. He wanted to move to WooCmmerce for that. Obviously the PHP scripts that used the Cart66 data was not capable of using the WooCommerce data.
The QURL solution
Based on the existing scripts used for the Cart66, QURL migrated not only the scripts to make it work with WooCmmerce. QURL also changed it from a stand alone script to a WordPress plugin.