The latest patch is f1.04.
The Fokker Dr.1 addon adds the Fokker Dr.I as a selectable plane. The Fokker requires the f1.04 patch.
The Adventure Builder Toolkit adds a mission editor (requires the f1.04 patch).
The official Adventure 6 Pack addon adds six new playable adventures built with the Adventure Builder Toolkit (requires the f1.04 patch).
Flight Unlimited II's San Francisco region can be played in Flight Unlimited III if you own both games.
Use dgVoodoo2 on Windows 8 and later.
These features are disabled in the game's 1024x768 mode. Use 800x600 mode, and use dgVoodoo2 to force a higher resolution
(N.B. you need to select one of the named emulated video cards (such as GeForce FX 5700 Ultra) in Dgvoodoo's DirectX options to make fog/haze effects work with dgvoodoo).