AND................ tow module works.
Definitely a HUGE oversight by Westfalia to not include in their comprehensive instruction manual to connect the two CANBUS wires/connectors. We attacked the interior panels this morning. 45 minutes later.... connected.
Coding (another story there) was completed by lunchtime, so Ivan and I went off and had an awesome pub steak lunch (you missed out
@evaddirb 
)
Took a moment this afternoon to connect the caravan (wiring) to the car. Hit the key fob to open the tailgate, and it unlocked and opened a fraction. Perfect. Checked the operation from the drivers door switch... same result.
So very confident that the rest of the coding is correct. Will know when I do a run to the landscape yard in a week or so with the trailer.
Thanks to all who offered assistance, coding etc. That is what this forum is all about, getting in and helping fellow members.
Cheers