[Zope-CMF] Plone add item restriction based on context/group/role?

[Ignacio Valdes]

Hello all, I would like to restrict what a Plone user can add based on 
the folder they are currently navigating in. For instance, I have a 
folder named My Protocols. I only want a user that is a member of the 
group 'Staff' to be able to add 1) folders. 2) CMFQuestion 
questionnaires and 3) a custom Archtype 'protocol' item to My 
Protocols and its sub-folders. No other items should be addable in 
that folder.

Similarly, I want to restrict the ability to add 'protocol' archtype 
to any other folder except My Protocols or its sub-folders.

In short, the ability of any user that is a member of group 'staff' to 
create a protocol should only be able to happen in folder 'My 
Protocols'.

How does one do this in Plone? Thanks!

-- IV