By Iain Withers LONDON (Reuters) -Morses Club’s shares fell by as much as 67% on Monday after a profit warning and the abrupt departure of its chief executive, who the British sub-prime lender said in a stock exchange filing had sold stock without giving it advance warning. Morses Club said in a trading update that a surge in customer complaints against its doorstep-lending unit “in recent days” meant that profit would be 20-30% lower than analyst expectations. It also said CEO Paul Smith had left with immediate effect and its Chief Operating Officer Gary Marshall would take over. Reuters was …