Lemme see if I can help a bit ... here are the info boxes from the installation order form:
Control Panel
Access URL: this is the URL where you login to your hosting account - should have been furnished to you in a "welcome" email when you signed up.
Username: your username for your hosting account
Password: your password for your hosting account
FTP
Hostname or IP: in most cases this is just your domain name - example: rosyswebsite.com
but if you have not done the Domain Name Server change (DNS) at the site where you *registered* your domain name - you will need to furnish the IP address instead of the domain name.
IP address will be a string of digits that are formatted with dots similar to this:
xxx.xxx.xxx.xxx
Username: this should be the same username you furnished above
Password: this should be the same password you furnished above
Install Dir: this box already has /mail embedded as a directory name - so just leave it as it is.
BTW - I've been using ListMail Pro for about 4 years. You're gonna love it!
Wishing all the best
Dan B. Cauthron