[Zope] Extensive Javascript GUI and security

[Tim Nash]

I have created a zope product that demonstrates how I would like to
use zope with extjs library. The demo does not require an installation
of extjs. It is linked to here
http://wiki.zope.org/zope2/HowToCreateJavascriptGUI

I hope that using zope along with extjs in this way makes zope much
more scalable however I am having trouble figuring out the proper way
to set up security.

Could somebody check out my demo and give me feedback on how to set up
the security?
I would like the user to only have to log on once. Subsequent AJAX
calls should not require subsequent log in.

Also, I create new accounts by copying an account 'template' folder
that includes a acl_users folder in it. How do you set the proper
security when you create accounts in this way? How do you set the
security on an external Method in these folders?
I want to use zope to hold medical data for everyone from a physician
in the remote regions of the World all the way up to multi-hospital
chains. This requires a very scalable and very secure zope.

Thanks for any help!

Tim