All old is new again
Setting Up Xash3D
Xash3D is intended as a replacement for the GoldSource engine, so the original engine binaries are not needed for Xash3D to work. Generally, you need only the following:
Installation for Pre-Steam Games and Mods
Installing mods on top of this setup is no different from installing on top of the original Half-Life. You simply need to put the mod data folder alongside the valve folder.
Installation for Steam Games and Mods
Xash3D does not work directly with Steam's *.gcf game data archives. To make a Steam-distributed game work with Xash3D, you first need to extract the game data from the *.gcf file using a third-party program, such as GCFScape.
Derivatives and Mods
Launching the Game
To launch Half-Life, run the replacement hl.exe program.
To launch a Half-Life mod, do one of the following: