If it is just for visualization, you could use ETC Eos software for free in the visualizer mode. This will distort the sACN once in a while, to prevent using it in a show. Otherwise, Qlab offers limited lighting capabilities.
ChamSys MagicQ. It is free and sends out 64 universes via sACN or ArtNet. And it it has also CITP protocol for direct communication with Capture. It can run in the same computer or on another one in the network.