Enttec datagate

i am working with the enttec datagate (ethernet input, 8 dmx outputs).
sending 8 universes (DMX artnet sender node) to the datagate. try to map the first artnet universe to the first dmx out, second universe to second dmx out,… 8 universe to 8 dmx out. sounds pretty simple. but somehow the datagate fucks up the dmx outs 1,2,3 and 4. 5,6,7 and 8 are o.k.
can someone give an example how to map (or copy) the artnet values in a correct way with the NMU software which comes with the datagate?
thanks a lot!
with kind regards,