Did you manage to solve your problem? I am experiencing the same problems.

After one more restart of Domoticz I can now confirm that it Smart Switch 6 together with Z-Stick works in Domoticz

I am using Z-Stick gen5 and Smart Switch 6. Using the version beta #4269 I am able to see the Smart Switch as a switch and not only V, A and W. But I am not able to control it. When I try to control it from Domoticz, nothing happens, but in the Open Wave Control Panel I am able to switch it on and ...