> I've used the "capture URL"
> and added the username and password, but site is not

On the Add Url popup, you enter the name/pass for http authentication OR click
and follow the Capture URL procedure.

Furthermore the URL specified does not have a form to log in with.

The log in form is at "My Account"
<http://myaccount.elegantmoments.com/order/login.php>

See <http://httrack.kauler.com/help/Authentication>