For nab.com.au, the login fails (id or password incorrect error) when the "auto-submit pages after filling logins" is checked. If I uncheck this option and manually click the submit button, it logs in successfully.
The password record is using a slightly customised Bank Account category.
Maybe it's due to there being no delay between filling and submitting? If so, the option to adjust the delay on a per-record basis would be good.
edit: specific URL is https://ib.nab.com.au/nabib/index.jsp