I've moved this to the Other Games board as it fits better there~
Unfortunately, as far as I know, yes that forum is down for good, but I know some IT servers are still up and running. Somewhere out there lol I personally don't have any files but I hope someone can help you out!
As for unleashed, it is by no means an official successor or continuation of FeralHeart. They are completely separate from us and are doing their own thing.
There are only a couple of IT games that I myself know of that are still going and somewhat active, and that's Dawn of Eternity and Glasmar. I know for sure that DoE is still releasing updates even.
As for FeralHeart Unleashed, as Ame said, they are not tied to this game at all, and the game itself is back under construction and is moving to UE4 and being rebuilt.