Although a “run::movie” option exists, there doesn’t seem to be any code in Rosetta3.0 that actually implements it. I would guess the option got moved from ++ without being implemented. If you want a movie in ++, you should ask on that forum instead?
If you want to make a movie in 3.0, all you need to do is find the loop in the code which represents the frames of your movie (this will almost certainly be a Mover::apply() function wrapped in a for loop) and then add in a pose.dump_pdb(“filename”) statement.