This is not a Super Hostile map at all! This is a training map, intended to give the casual Minecraft player a (small) chance at lasting for more than a few minutes in my actual Super Hostile maps.
Currently it only has a few training areas, but future versions will add things to the training course. If you are a veteran player, and you have a suggestion for a training area that I should add to the map, let me know!
Copy the zipped map file *as is* into your Saves folder. The next time you run Minecraft, the map will appear under your Saved Games.