Well with your original problem of your old FH deleting itself, your files might have seen a copy and deleted so there wouldn't be an FH copy. Did you ever get a little pop up that said something like, '1 or more files already exist in this folder'. If so, did you push 'Replace files'? That would have deleted Feral heart. But FH also might have deleted itself because you already had it installed. Feral heart wouldn't work if there were two FHs with two sets of files. So that might help your first confusion.
If you DELETED everything in your materials file, then Feral Heart will not work that I know of. I suggest finding someone who can put up all the original material files for you for download. Then see if that works.
Hope I helped a little with your concerns.