[Zope] Create User in DTML question

[Marc Stein]

I have a rather involved registration process in which users enter
information via multiple forms.  This information is then stored in a user
table in MySQL.  Upon completion of the registration process (and at
subsequent logins) the user should be able to access a registered user area.

It would seem to me that my options are to create the user in MySQL and then
additionally create that user in acl_users or to authenticate the user in
MySQL and not use the user folder at all.  It seems fairly easy to create
the user within the user folder with the manage_users method except that I
have only gotten this to work if I set the Manage Users permission to
Anonymous for the registered user's directory.  This doesn't seem
well-advised.  Is there a way to execute the manage_users method as a
Manager from within a DTML method?

If I authenticate the user using the MySQL user table can I then set that
user as Authenticated within the SESSION object so that they don't have to
re-authenticate within that session?

Towards this end, when a user comes back and enters the registered user's
area they will be prompted for their username and password.  How can I
access the username that they entered?  Is it within the REQUEST.SESSION
object?  Is their a way to override the username/password dialog so that it
asks for "email address" and "password" instead of "name" and "password".

Many thanks in advance for any suggestions that anyone can provide.  This is
my first project in Zope and I'm rather fumbling along.

Marc Stein