Keeping it running doesn't appear, in the UK, from the information you provide to be a crime unless it is done dishonestly to defraud creditors (fraudulent trading), and mere current inability to meet payments isn't enough. Lots of acts done with intent to defraud are criminal -- the fundamental wrong criminalized is fraud.

Mere trading while insolvent, without dishonesty and intent to defraud, appears to be an unlawful-but-not-criminal act that results in personal civil liability for company debts. "Unlawful" and "criminal" are not the same thing.