CMS Permissions - Unregistered can't see previews?

[HouseAddict]

Ok, this is just retarded - I spent a whole day today trying to get this working and still nada... zilch. This really shouldn't be that hard to figure out, so here, I'm throwing in the towel and asking for some help instead...

If I've got a root Section with "read" permission enabled for all usergroups, and a sub-Section that has read permissions enabled for Admins/Mods only (meaning, Unregistered users are not able to read the content), how can I actually have that sub-Section show on the front-end for Unregistered/non-logged in users (in the Sections widget/nav on the side) as well as show previews of all the content with thumbnails in the grid layout (default action when browsing a section) but prevent them from viewing the full article (as in, that's when that login/register error message should kick in)?

As it is, right now, it's all either black or white, there is no gray area where I can show certain usergroup what is available in the CMS (like I can in the forum) without letting them view the full content... or am I just THAT blind that I can't figure out the right combination of settings and permissions to get this working?

HELP!