Empty Content cart on 1.5.5.1

Hi,

I want my website to have the feature of removing the content of my cart with one button.

I've bought this extention: http://codecanyon.net/item/opencart-one ... ty/5681925,
But it doesn't seem to work or do anything at all?!

I've also tried this step by step tutorial with no luck..
http://patrick.bloggles.info/2014/01/01 ... art-store/


Does anyone know how to make this work on my website: http://www.fadshop.nl, Opencart 1.5.5.1?

Thank you in advance!