No, the dealer didn't copy the letter to VW UK. VW UK rang me to find out if the letter arrived, they didn't know what the letter said so I told them on the phone and said how angry I was. VW UK apologised for the dealer not giving a satisfactory answer.
VW UK are very good at chasing the dealer and getting them to phone, write etc, however they don't seem to have been able to influence the dealer so far. I'll send a copy of the letter to them today and also let the know that TS are now on the case.
I have to say CAB gave me a quick response by email and informed TS straight away, TS were very quick to respond and very keen to get involved. TS said that they would review my paperwork the visit the dealer to look at their paperwork and find out why the dealer didn't disclose the import status, specification differences and the resulting difference in car value when I bought it.
I'm feeling slightly more positive now, fingers crossed for a refund, the only problem then is finding another car to replace mine!!