I live on the other side of the world from Corsair so they will hopefully respond over night.
It's good to know that Corsair's customer service is held in such high regard. Gives me some hope that I will be up and running again soon.
After taking what I hope was enough photographic evidence, I removed the cooler. I would have thought that if it leaked anywhere it would have been where the pipes connected to the block, but it seems to have leaked along the seam on the block: