Hi Jay,
Thanks for the message. Russound is currently not supported on Control Cube. The only way you can do some kind of integration is through VERA scenes. For example, you can set up a scene to play X source at Volume 40%. Then simply add the scene to control cube.
Sorry, but the only sound system currently supported is Sonos. I honestly have not had any experience with Russound.
All the best,
Hadi