Details on how to install can be found in the READ_ME file.
This map is basically a more difficult (and darker one too) version of the official level "Cooler". If you consider yourself a decent Far Cry player, you have to try this challenge. I can verify it can be done on Realistic too (I've managed to do it on Realistic myself). I hope you are gonna like it, it took me a bit more time than you probably think. Done in the Editor.
A harder version of Fort is coming up really soon, so stay tuned.
Thanks for your time.