Newbie help with Hercules Dual 15A 6-20V Motor Controller

I am totally new to all this and need some assistance. Been Googling for 2 days and not finding anything specific.

I have the Dagu Rover 5 4WD Tracked Chassis, Hercules Dual 15A 6-20V Motor Controller, Spider Controller - Atmega 1280, Spider Controller - HD Servo Shield and Arduino Uno - R3

First step is to determine how all this connects to each other.

Focus right now is what pins connect the Hercules Dual 15A 6-20V Motor Controller to the Arduino Uno - R3
I’m (temporary for testing) powering the Motor Controller (without connecting anything else yet) with a 12v7ah battery through J1 (GND=GND, +=VM) On connecting board PWR Led does light up. Pressing RST Red LED lights up.

Based on what the wiki example for the Motor Controller says when connecting to a UartSBee I am assuming the following needs to be connected on similar basis:

Pins on Motor Controller: Pins on Arduino:
DTR No such pin so do not know
TX RX (assumption)
RX TX(assumption)
5V 5V
GND GND
GND GND (not sure if both these GND need to be connected)

If above is correct then I’ll power up after connecting the Arduino to my PC via the USB port.
If that then is correct I’ll connect up the Encoder and DC Motor cables to the Motor Controller. (those are quite clear on the wiki) Once I’ve done that successfully and can control the DC Motors correctly I’ll work out how to connect the Spider Controller.

Sorry for noob questions just don’t want to break anything.
Any assistance or links is greatly appreciated.