ok do this then, do what I said, to get the door lock open, then on the side of the door (that is hidden when closed with the body work, there is a grommet covering the screw for the handle (think its an allen key) open this, slide the handle to the front of the car, then pull out

check if the barrel is breaking/broken, if so, then it is £1.50 + £1 (for barrel + spring, from SEAT dealer)

for the mean while you can swap the passenger door with the drivers so then you can use it :)

hope it helps
 
I've had no luck opening the lock.

I took the pin off and and then the pin surround. I then tried to use a needle nose pliers to pull the lock up.
Couldn't get a grip on anything. I can hear that there's something moving around, but I can't grab onto it.

Any other suggestions?