I have a Sratus with ZWave and have the same question. I can't figure out how to use it.
In fact, I can't even figure out how to verify that the plug *has* Zwave in that I don't see any devices or files with the word Zwave in it. Nor is it mentioned in the /sys/devices tree.
Have you been able to get *anything* out of your Zwave plug -- even if just to verify that it has a Zwave module?