Thank you for your interest in our services. We have lots of non-profit organizations and business start-ups (with remote team members) using our services. It is a much better solution than any in-house solution: You save on email and FTP server hardware + software; no need to setup firewall security, accessible from anywhere, etc.
To setup custom domain email, you need to own a domain name. If you don't have one, you can order it from any domain registrar companies, such as Register.com and network solutions, etc.
Once you have a domain, you need to configure the DNS. Almost all domain registrar companies offer basic DNS service. You need to add an MX record and an A-Record. The MX record should point to a server name that resolves to 126.96.36.199. Please feel free to contact the domain registrar company for support.
Please note DNS record takes about 24 hours to refresh. Once this is done, please visit http://www.drivehq.com/Email/, log on and then click on "Private Domains" link. Follow the instructions there.
As of discount for non-profit organizations, yes, we offer discount for non-profit organizations and educational institutes. The requirement is you must order a service plan higher than 20GB, and we offer 50% discount for additional services.