Silicon Labs' official GUI controller (Simplicity Studio): implements a Z-Wave controller node over the Serial API of a UZB USB adapter, so you can include/exclude nodes, browse the device's supported command classes and send them, driving a Z-Wave network legitimately from a PC. The application-layer counterpart to the Zniffer's capture.
Lifecycle not assessed: nobody has checked yet whether this tool is still maintained, sold or working. Check the project's own page before relying on it.