I don't follow all the detail of the discussion above, all I can say that it's very counter-intuitive to apt-get install the plone package, then have to make your own zope instance (at least you're told you need to do this) and then log in to http://localhost:9673/manage to discover that there is no Plone site product to add :-(
Why not uncomment the Debian specific # products /usr/lib/zope2.7/lib/python/Products line from the standard zope.conf? It took me a while to find this and it would be nice if other Debian users didn't have to spend this time as well. I gather this may be a compatibility problem with other versions of zope, but at the very least adding a line about Plone to the cryptic, "You may want to customize /var/lib/zope2.7/instance/<instance>/etc/zope.conf" would make a big difference. Thanks for your time, regards, Pete

