How to include group access level in a ws call

Question

I want to include a Group Access Label in a Permission for a Course using an iTunes web service call.
I don't see how to do this in the docs.
(The example in iTunesUAdministratorsGuide.pdf at page 111 doesn't include the Group Access Label.
And it's not in the schema for the ws xml document at http://deimos.apple.com/iTunesURequest-1.0.xsd)
Is this an obvious omission or am I missing something? Anyone know how to do this?
Background:
We're creating most Courses programmatically.
Obviously, we'd strongly prefer not to require an administrator to go into every Course and manually add a common Group Access Label to the Permission. (This manual piece is essentially what's now missing from the ws call or at least from my understanding of it.)
Either way -- manually by an administrator or programmatically -- our instructors would then be able to set Permissions themselves on any Group they create -- doing this themselves and without the help of an administrator.

Answer 1

To resume with a little progress made:
I have a Section
* with Access Level == Edit for Credential == Instructor@...${IDENTIFIER} with no Group Access Label, and also
* with Access Level == Download for Credential == Student@...${IDENTIFIER} with Group Access Label == Student.
I'm doing ws calls to add a Course including an identifier. This is successful, and I can then go into the iTunes client as Instructor@...${IDENTIFIER} (substitution made) and manually add Groups and change Access to each individually. (I'm adding Groups "Download", "Shared Uploads", and "Drop Box", changing the Access Level accordingly for Group Access Label "Student".
But naturally I want to do the manual part programmatically, to save n instructors from having to learn how to do this same thing and then to do it.
So I'm trying to change my ws call to add the Groups, including Permissions. Schema http://deimos.apple.com/rsrc/xsd/iTunesURequest-1.1.xsd doesn't include Group Access Label for Permission. What does this mean?
I've tried the actual Credential == Student@...${IDENTIFIER} (with IDENTIFIER substitution made before the call) and also Credential == Student (to see if I'm supposed to match the Group Access Label, instead).
For either of these trials, the ws call successfully adds the Groups and a ShowTree includes the Permissions for the Groups. But in the iTunes client user interface, it's as if I gave no Permissions in adding the Groups.
Am I approaching this wrong or is there a bug here?
(I haven't tried yet a separate call to add the Group Permissions, not wanting to suffer the processing wait of getting handles for the three Groups.)
Anyone else doing this? (successfully or not ) Thanks.