After 1.5 years... It's back! Fixed some mapping bugs, added barnacles, NPC rushers, some alternative ways, scripts, steam icons, final speech (lame one, but I did everything I could) and final music by Toni Karengin. Installation instructions below (click the "+read more" link).
How to install:
WON version (up to 18.104.22.168):
1. Close your game.
2. Extract the archive you've downloaded to your Half-Life directory (e.g. C:\Sierra\Half-Life) so the end result should look like this - C:\Sierra\Half-Life\zombie\ (there should be no C:\Sierra\Half-Life\zombie\zombie folder or C:\Sierra\zombie\ folder)
3. Start Half-Life, go to "Custom game" and select Half-Life: Zombie Edition from the list.
4. If you can't find it on the list, try creating a shortcut to your hl.exe application. After you've created it, add " -game zombie" after filename in shortcut options.
Steam version (22.214.171.124):
1. Close your game and Steam.
2. Extract the archive to your Half-Life directory (e.g. C:\Steam\steamapps\yourusername\half-life, so for me it'd be C:\Steam\steamapps\shooter__andy\half-life) so it should be like this - C:\Steam\steamapps\yourusername\half-life\zombie\ (there should be no C:\Steam\steamapps\yourusername\half-life\zombie\zombie folder orSteam\steamapps\yourusername\zombie\ folder)
3. Start your Steam client again.
4. Now you can either make it so you start Zombie Edition when you start Half-Life, or you can create a shortcut to the mod directly without changing the original game:
4.1. For the first option, go to your games library tab on Steam, find Half-Life, right-click on it in the list, select "Properties" and then press "Set Launch Options" button. Add "-game zombie" without quotation marks.
4.2. For the second option, create a shortcut to your hl.exe application. After you've created it, add " -game zombie". Add it on Steam ("LIBRARY" -> "Add a Game" -> "Add a Non-Steam Game", select your shortcut) and do what 4.1. says for this new game.