I just don't like that this is centered around Cthulhu only in its name, Cthulhu was a single character (and community blew it to a proportion of "myths"), it's like calling a Tolkien world "myths of gollum".
From what I've seen, both "Cthulhu Mythos" and "Lovecraft(ian) Mythos" are equally recognizable...
But it seems the folks who refer to it as "Lovecraftian" usually get their start in the books. While the folks who call it "Cthulhu" usually get their start in games and movies.
I've known several people who played "Call of Cthulhu" and saw various movies featuring The Necronomicon... But never knew who H.P Lovecraft was.
Lovecraft referred to it as "Yog-Sothothery", but the whole thing is difficult to pin down, since he shared it with other writers, some of which added good stuff, some of which added bad.
Which is really what gave the mythos legs.
There've been plenty of authors over the years who turned out plenty of interesting settings and monsters and stories... But those settings/monsters/stories are largely contained to that one author's work. Lovecraft actively encouraged the sharing of ideas between his author friends. He gave them ideas, they gave him ideas, and you wound up with this extensive mythology that spread through all sorts of weird fiction.
The roots go so deep that it's almost difficult to find modern supernatural horror that isn't touched in some way by Lovecraft's mythos.
Anyway, this sounds like an awesome mod. I wouldn't be at all surprised to see one of my dwarves dig a little too deeply and break through into some ancient ruin full of shoggoths. Maybe replace HFS with eldritch horrors of various types? Seems like a perfect fit to me...