I would like the option to not allow users to create their own accounts. Is that possible?
Can I use LDAP or some other data source for user authentication and rights/roles or am I restricted to using the built-in user auth and permissions?
LDAP pluggin is not done (yet) we are waiting for a contributor to start working on it.
For the user creational option, this should be a matter of configurating the UserModule and have the UserPortlet check this parameter. It is not implemented so far.