Mindboards

Ok so i am probably in the wrong place but anything is worth a try.
My daughter built the alpha rex and had it working and moving.
Then it stopped working when you run the file the square just keeps moving and the robot twitches a couple of times and makes a high pitched whistle?
We reset the brick as advised by lego reloaded the firmware and reprogrammed and its still doing the same thing.
Can anyone help i have one really frustrated and disappointed 9 year old.
Thankyou

Suggestions:

One: Did you make sure that the batteries are fully charged?
Two: Is the mechanism jammed? Can you move it by hand?
Three: Did you set the motor power levels in the program correctly?

I was all working fine the batteries are brand new and the power indicator is on full