A 3-cell AA battery box is included, however this makes the motors very underpowered so we recommend using a 4-cell box for alkaline batteries, or 5-cell for rechargeables
If any of this is of help and you can advise me, thank you.
The 9v battery powers the Arduino no problem, why would I need to change that?
Also, test run the motors directly from the battery. Run OK??
I got the kit with absolutely no instructions, or info on the motors. I built the kit using the pictures from the link I posted and followed all the instructions regarding installing the motor shield and uploading the code. I don't have a meter to test the battery voltage when the motors are switched on.
Here are a couple links to some basic tutorials