Woah, this is insane!

This is why I tend to like older Audis, typically B5's and prior as they have less things to go wrong and still feel like a more solid car. (Hence why I have a B5) - Next car will either be a second older Audi or something BMW/Mercedes I think.

ALL newer cars tend to be plasticy and rubbish, Audi's seem to be no exception to this rule. Obviously Audi Melbourne are being complete idiots about this, there's quite obviously an issue with your gearbox/clutch and you need to keep harassing them until they fold. Do you happen to have any paperwork (or remember the person) that you were talking to from when they said that they'd replace it under "goodwill".

Some solid advice has been said in this thread; mostly within the post above mine. I'd honestly get the car fixed (if you can) and then sell it and buy something else Euro that you like out of spite/for your Sanity.

I personally would be going to another Audi Centre if possible (I'm sure there are heaps in Melbourne) and letting them know about your issues. It may just be a specific $tealer$ship issue and not Audi themselves. This might get you further than what you've been so far. The longer you wait, the less chance you'll have of getting it fixed under "Goodwill".

Do also remain calm, in saying that I am not saying that you are an aggressive person. Just that if you remain calm and get along with the service center employees that you'll likely get somewhere quicker. I've worked in retail before and it is a LOT more pleasant to get something fixed for someone that you can get along with and relate to.

Anyway, I wish you the best of luck getting your car fixed!