passenger front door locks but won't unlock

I can't figure out how to get that little black clip off the yellow holder to release the bit going to the door handle . any tips?
OK i figured that out for the lock out put in one bought from eBay and boom still the same problem, door will not unlock from the outside. So either the replacement second hand lock has the exact same problem or something else in the system is broken. Any ideas? Or do I just need to bite the bullet and order a new one from Audi :(

Do I need to clear anything with vcds? I can borrow a cable from someone and try that tomorrow