Very successfully on the Homeseer Zee with the Blade BLRussound plugin! Blade recently made some improvements to the plugin. Most notably, the ability to change/select the channels on the ST-2 XM tuner. I use the XM tuner with my HT set up independently of the whole house Russound CAV. He added the ability to turn on/off and control the XM tuner for that purpose. The CAV doesn't need to be on.
Just a heads up, since I also control the Russound CAV from the Omni panel, and only one of the CAV's serial ports can be used at a time, I connected the IP-Serial server to the ST2-XM tuner's serial port, and it transmits sigs to the CAV without issue.
There are still a couple of very minor issues with the plugin. For example, when you first turn on a keypad the volume setting in HS doesn't update. Any subsequent action on or to the keypad updates the HS device values. He likely needs to poll the keypad for its settings when initially turned on.