security assist cannot password protect a folder, it can only password protect the pages. Security assist uses PHP code. You cannot add PHP code top a folder. You can only add php code to a php page.
you can use .htaccess to password protect a folder. theres no problem in using the 2 systems together, but they will be separate logins. You will need to login to the folder, then login in again to access the pages.
to store the users IP address, you would need to bind the ip address column to the REMOTE_ADDR binding in the server variables collection.