It might be much easier if you just use DriveHQ FileManager 4.0 client software. No configuration is required as it is preconfigured to work with our site.
If you really need a third-party FTP client, the info is available below:
FTP server: ftp.drivehq.com
Port: standard FTP port (21)
Username / password: sign up free on DriveHQ.com
Start directory: no need to enter; or enter "/" as with DriveHQ FTP, you get a full-featured FTP virtual server hosting service. You can have your own root folder. You can also share files to other people.