The server runs a modpack that will need to be installed before you can connect. The only way to download the modpack is with the FTB client.
The FTB client will download all mods, and manage the launching of the game without needing to worry about installing and running modded MineCraft.
The modpack will download and be avalible to run on main page of the FTB App once installed.
Follow the normal install instructions, then copy these files and folders from the old instance folder to the new instance folder.
(Skip any missing files or folders in this step.)
To connect you will need to add the server to the multiplayer config.
Select 'Multiplayer' on the main screen, and then select 'Add Server'.
Enter the following details
The server is a whitelisted server, this means that your access must be granted. To request access you will need to send the following details to ‘nightred+zealmc [at] gmail.com’.