I use the zooz 700 stick...It should be powerful enough to connect to your switches, especially if it's centrally located.
Use the guide here...It also shows firmware updates. Once it sees your devices, simply pick the device, click firmware update, it will ask the location of the firmware update file and you pick it and click update. Follow the stick firmware update instructions just pick your switch. Z-Wave Ghost Removal using a UZB-Stick - How To
