After stripping the door card.
Look at the wires going to the motor assembly and use a small 12v battery.
I had a ride on Lawnmower battery to hand and directly powered the lock to unlock it.
After that I stripped the mechanism down and somehow disabled the superlock.
It's never done it again in the 4yrs since.
If..... You don't feel confident doing it, don't. I wouldn't want you to cause further problems for your self if your not 100% sure.
If you get to the point were the card is removed and get someone who has more knowledge to help or if your good and confident, try it yourself.