Local DMX

Hi - Im trying to recieve DMX / Artnet from MadMapper, running on the same machine.
I hoped that connecting to a network switch would allow me to setup both apps.
Madmapper allows me select the LAN port as an output, but VDMX is not spotting the IP address. Any help appriacted, i wonder if there is a local host option - but eventually i want the artnet from MM to go to VDMX and to a lighting desk.
I have tried various options of boot order of the apps and rebooting the machine.

So eventually some combination of changing to a new ip address and rebooting - kicked the network into action and VDMX & MM both see the port.
I can see Artnet signals on an artnet viewing app - so know its getting out of mm, but im not seeing any DMX in VDMX detects
Should i see the channel vales changing in DMX prefrence pain ?
Am i missing somthing in the VDMX setup?
cheers Howie