In general, you can always rate all the boxes and products on the website that you have received. Just go to Past boxes and click on the box you want to rate. You can then leave a review by clicking Write Review in the bottom right corner. 

You can also rate each product in the box by clicking on the product in the box. On the respective product page again click on Write Review in the bottom right corner:

Important: Please enter the same e-mail address as you used for your order so that the CURLCREDITS can be credited to your account and displayed as "Verified". After each review you will receive a confirmation e-mail that you have just collected 200 CURLCREDITS :)