.. and if you do try to use it at the last minute and get a glitch on your password (you think) try not to request another one as it will be forwarded to you in an email within the next 48 hrs ! What you preferably need is an eAPIS System Administrator to bail you out. The local CBP office might know the number of a friendly one. Or might not.
You really need to check that your registration to the eAPIS system is working a couple of days before it is needed for real. Should save some of that familiar last minute panic feeling.