the currently logged in user is determined by a session variable that is set by the log in page.
in the insert behavior, the id of the record that is created will also be stored in a session variable.
I would bet that the name of the session that the Login page creates is the smae name as the one the insert creates.
on the insert page, change the following line:
$WA_sessionName = "SecurityAssist_UserID";
$WA_sessionName = "insert_SecurityAssist_UserID";
so that it is creating a session with a different name.