It would not surprise me if the cars would be impossible to register now as they could not be made to comply with the current emission standards for new cars.
Such a shame that they were not able to succeed. The body styling looks very nice.
They would probabaly be registered via an IVA process. This requires that the engines meet the emissions requirements relevant to the age of the engine. At least that was the case, I recall there was a proposal that IVA'd cars should meet current emissions requirements but I do not know if that came to fruition.
Edit It looks as if the proposed change did not make it into legislation. from the Gov.uk website "For spark ignition engine vehicles the emissions test is based on the age of the engine."
