Looking at the code on code.mios.com, this plugin is very rudimentary. It exposes a small handful of media actions from the MCV set (Play, Pause,etc) that the SQBlaster will see, but none of the Power management (Discrete On/Off or TogglePower) or Volume control stuff from the MCV interfaces.
It does expose a rudimentary UPnP volume manager, but that's it.
There was talk a few months back about merging the SB variant plugins, since they were each implementing fragments of the total picture, but not sure if that effort is moving forward or not.