Hari:
Are you looking into revisions of the ZWave package? Its pretty old and doesn't support the latest revs of the ZWave protocol. It also has some annoying bugs (like dropping ZWave devices if there is a gap and reinstalling them). And still only support for the obsolete and rare Homepro USB_ZWave interface and the even more rare Boca USB-ZWave interface.
The real problem is finding drivers for the other's USB interfaces that work in Linux. If someone can find a Linux driver for the chip in the Intermatic or the Cooper or the Wayne Dalton we can make them work, but up until now no one has a Linux driver that works with those. I can provide details on the chips in them if anyone is interested.