Sorry, I can't remember how the outside one hooked up to the central locking block exactly....
To take the handle out you need to undo the top torx screw on the side of the door (i.e. where the lock catch is).
Then you might already see what's gone wrong. If not it's a job of removing the central locking block, part disassemble and clean.... usually having to pull hard means that some of the mechanics are either frozen or seized up.