security assist does not rely on the register_globals setting being enabled.
it does rely on the $_GET, $_POST and $_SESSION supper globals though.
the register_globals = on setting only creates a friendly copy of a supper global that is set.
for example, if a session is set:
$_SESSION['mySession'] = "my var";
with regerster_globals = on, you could echo the session using either:
or the friendly variable name $mySession:
turning registeer_globals off prevents the friendly variable $mySession from being created.
The register_globals setting is deprecated in php 5 and is not replied upon in Security assist
register_globals is not the cause of whatever issue you are encountering.
the first thing i would suspect is that the server will not properly store sessions, to test the servers session management, use the session test page from the following thread: