In the help files it says to “enable impact feedback checkbox” in order to have cloth -rbd interaction in both ways. (or with flip or wiresolvers) but i can't find this checkbox.
Where should i look for this?

It used to be on the Cloth Solver DOP, but I'm not sure where it is anymore. I'd at least log a bug for documentation.

Up? Would like to see this come back in some form xD
I read on the docs that to make Cloth and FLIP mutually affecting each other, to deal with the changing topology of the FLIP, one should create an attribute called “previous” that's storing the position of the particles in the previous timestep.
I tried to di this with a sop solver in the dopnet, but nothing changed

Any clues, tips or examples? Thanks!