Trick with Aeon Labs DSD37 ?

I’m trying to add one of these range extenders to my Vera3. It refuses to include. Is there a trick to this? I’ve tried low power, full power. I’ve excluded it first (which works just fine… Vera seems to ‘see’ it long enough to exclude it when I hit the zwave button on the range extender). But any attempt to include it simply doesn’t work. The Vera just sits there looking, and the red light never stops flashing. Eventually, Vera comes back after it times out and says it can’t find any new devices to add.

What’s the trick with these? Or did I just get a dud?