I just order this "plug-in" script. It's not a shopping cart. It's only a script that works with the joomla article. I've spend hours on the forums trying to figure out how it works. It's not a module or it's not a component. I'm not going to give it a rating because I have little knowledge of joomla and script writing so it may not be fare. I would suggest stay away from this "If you think you’re getting a shopping cart”.
On the contrary, this extension provides a very nice shopping cart and is very easy to install and use. We offer FREE technical support for all of our extensions. Why didn't you contact us or use our support forums? We are always happy to help people like yourself who need a little assistance to get things going.