Project lead Interkarma has written an extensive guide to installing Daggerfall Unity here.
Daggerfall Unity is an installation of two major components:
- The original Daggerfall's files
- The Daggerfall Unity game
Depending on your operating system, your installation method will vary.
Step One: Windows
The recommended installation program is DaggerfallSetup.exe. Use it to install Daggerfall somewhere on your hard drive. You don't need to change any mod or patch settings as it installs. Some graphical changes carry over, such as the Dark Elf patch for Wayrest nobles, but most other patches won't have an effect in DFU.
Step One: Linux and Mac
Since these operating systems can't run DaggerfallSetup, they need to obtain the files without an installation. Interkarma has made available the necessary Daggerfall files on the Live Builds page. Place these files in a folder somewhere on your hard drive.
After the Daggerfall files are on your hard drive, extract the Daggerfall Unity zip into an empty folder. Run the Daggerfall Unity application. It will ask you to find your Daggerfall files. When you have found it, the window will turn green and you can proceed to configuring your video and other settings prior to starting the game.