I kept a car I was selling in a garage without insurance for a few days - did I commit an offence but not submitting a SORN?

I recently kept my car taxed but not insured in my private garage for a few days before selling. I took temporary insurance to demonstrate the car. Did I commit a criminal offence by not submitting a SORN?...

I sold a car 'as seen and approved' but the buyer now claims there are faults and is demanding money?

I have a 'sold as seen and approved' document from a sale I made recently but now the purchaser is demanding £500 for alleged faults. He wants to take County Court action against me. What are my rights?...