Hello Palliser
My; that looks a lot neater, and hopefully stop any gremlins with wire lengths.
It will be interesting when you receive the DM9161, is this mounted on a carrier with the jack/magnetic's similar to the DP83848 board ?
The POE is very easy to achieve with suitable Jack socket, as similar to the Arduino Ethernet, and a ready built POE module can then be soldered in
these can range in voltage from 3.3V upwards so can be selected to give the voltage that's required and additional Voltage regulators used for lower voltages if needed.
some such as the silverline range can have there outputs modified, the usual 12V from the 9012-S POE module is reprogrammed with a shorting link to only supply 9V so not to overheat the fixed 5V regulator on most of the Arduino boards.
I'll keep and eye open for developments and wish you success
BR
Graham