Hello! I've got a pretty simple problem for the Houdini masters out there. I have a fractured object setup, and I want gravity to affect part of my fracture and not the other part. The idea is, I have a tornado and a house that is crumbling in my scene, and I want pieces that crumble off to fly into the air. I reverse the direction of the gravity, though with my current setup, the entire house starts to fly into the air, instead of the pieces that crumble off. I'm sure this involves specifying those crumbled pieces in the gravity force group parameter, but I can't figure out the proper syntax for the simulation to work. Perhaps I have to use the group dop node as an intermediary? If anyone has any ideas, I'd definitely appreciate the help. I've attached my scene file for anyone brave enough to venture inside.

Thanks in advance!