If anyone else is interested, this is how to set it up for ethernet connection between modules, look like a bit of rewiring is going to be needed first for me:
That only applies to router mode, not access mode. You will be operating it in access mode, so that would not apply.
" When the Deco is set to work under Access Point mode, you can wire satellite Deco to any Deco unit or the main modem/router."
Obviously make sure you have changed it to access mode before connecting another node using Ethernet.
