Here's a new old interview with Charlie, over at Future Movies. He gives another brief comment on the mysterious horror project:

I am writing a scary movie right now but I have no interest in making a genre horror movie, so I keep trying to make sure that's not what I am doing, so I keep trying to figure out what's really scary, not what's scary in movies because that is too easy, and it's a real struggle, but it's a struggle that I choose.

Have a good day.