BUT, when our son finally gets going, it will not work as it is supposed to.

He gets started, but his caracter may go forward for a short while, and even
go to attack on one or two yellow pigs (? As a mum, I simply dont understand
better, it seems like a yellow pig =-) ). But then, the caracter´s attacks i
useless. Either it doesn´t do any attack, it doesn´t move at all or its
attacks are of no use, the yellow pig seems to be unharmed and after a few
seeconds the pig kills the caracter. In worst case scenario, everything gets
hooked up, and noting more happens at all, it isnt even possible to log out.

What is wrong?