Z-stick Range Issues

I bought a Z-stick from Micasaverde, though I’m not using it with the Vera (running it with Linuxmce instead)

Having experienced terribly unreliable performance from the unit, I ran the following experiment:

-I unpaired all my devices except for my 4 HomePro lamp modules, which I plugged into a powerbar on a long extension cable.
-I programmed linuxmce to cycle all the modules on and off repeatedly
-I started standing next to the Z-stick, and backed away slowly, watching the flashing LEDs on the modules.
**The modules began experiencing intermittent reception past about 6 feet.
-I took node 1 off the powerbar, and plugged it in next to my linuxmce box (with the z-stick) to have it act as a repeater.
-With the remaining 3 nodes, I repeated the experiment.
**I was able to walk anywhere in my house and still get reliable reception.

I have to conclude that there is a problem with the transmission capabilities of the Z-stick I received.