Shop On Facebook

I can not create a store on facebook with the widget, it gives me the following error:
This page does not have permission to install the custom tab.
I created an app and inserted the url and it works, but I want to use the add of cscart with the widget, I read that with the multivendor you do not have to buy the license, possible?
Thank you

Has anyone integrated the store on facebook?

also who owns the multivendor version must buy the facebook app?

I have issues aswell:

API Error Code: 191
API Error Description: The specified URL is not owned by the application
Error Message: redirect_uri is not owned by the application.

You must have 2000 fans on your page to integrate the store on facebook.