A quick update. Sent off the first version of the main daughter board via DirtyPCB this evening. Here's a little screen grab from their submission tool:

This board contains the main electronics to control the camera, camera servos, rov-buses, power input and monitoring, LED brightness, monitor humidity, temperature, vessel pressure, and IMU. There's also some tidy space to mount the usb-to-ethernet and ethernet-to-powerline adaptors.

Much more about this board next week ... assuming it works.