Trying to create a group for thumbnail only access?

[crl]

I am trying to create a membership group named 'Basic Membership' that can only view the thumbnails and not the intermediate photos. I created the group (see pic) and selected the thumbnail only option, changed the members concerned details to the Basic Membership group. I created a test account to check if it works, but it doesn't, Basic members still have access to the intermediate images.  So what could be wrong?

[crl]

It was a simple mistake.  I had two groups ticked at the same time, registered and the Basic Membership