The ns_training_1_setup.exe file you have requested: Mods / Multiplayer / Natural Selection / Maps / Training / Natural Selection: Training Map - 8.86mb is not available. Perhaps try browsing all files for the game Half-Life and upload any files you want to share or are missing. This is the only information we could locate:
Meat_Popsicle, the original creator of this map took him 4 months to create this. This is one amazing map that should be checked out by everyone, even those who already have played Natural Selection for a long time. If a beginner player will play this map and finish it, you can be assured that the new player will learn a lot more about the game. Do remember that this won't be a map that you can just install and select the map in game. Let's say this acts as a mod, so this shows up in the Game List in Steam.