CMS Made Simple Forums

I need a shopping cart for a website I'm building for someone, so I decided to try out ESShop.  I couldn't find any way of installing it under the Modules Manager so I downloaded it from the CMSMS website, extracted it, and FTPed the files to a folder under the Modules folder called ESShop (ie. modules\ESShop). 

I set the appropriate permissions but now I'm not sure how to actually install the module.  It doesn't show up under Modules Manager and I can't find any instructions on how to install it (I searched the forums but couldn't find any).

Could anyone please advise. 

Thanks.

Regards,

Steve