Hi, i´ve got the cube also and made some flows for my ceiling lamps in my living room and kitchen (basically the same room)
rotate dim down, just set a relative brightness and also you can see from the tag menu what the values are when you rotate the cube.
This is dim up function. (below)
You also need to take in consideration that when you rotate the dimming does not happen in realtime, there will be a little wait time from the rotation to the execution.