I have one of these devices and have had a big struggle. Just want to share my experiences so far. I have the new version of this controller with the 2.0 firmware. I do not know if these two versions behave differently, as Aeotec does not give it a new model number i expect that these behave identically, but the hardware is different, because old wallmotes will be bricked with the 2.0 firmware, and new wallmotes gets partially bricked with the old firmware.
It works as a dimmer via association group, directly controlling a Fibar dimmer 2. I can dim it up and down by holding a button, and turn it on and off by touching the button lightly. This means that the OH2 binding correctly configures the switch with the association group config when using multilevel.
However it does not work to when trying to use it as a controller for a basic on/off switch using association group. I have several Fibaro wall-plugs which are on/off, and as others here as well have tested this does not work.
I find it very strange, as association group is supposed to work directly between the switch and the control, with oh2 just as a configuration interface. If the z-wave plugin manages to configure multilevel associations correctly then it is strange that on/off associations does not work.
For me direct associations is essential for parts of my house, as it gives redundancy if the OH2 server is down.