Regarding the law , we have had several qualified legal opinions now and it seems as if section 32 of Limitation Act 1980 is valid in our case. This means we are fighting this based on breach of contract, breach of several sections of the sale of goods Act 1979, breach of duty of care i.e. negligent & breach of AWS code of conduct.
The Expert and others are incredibly helpful to us, but the amount of time we have had to put into this to gather all the necessary evidence has been exceptional. The Letter of Claim is in the post.