Central Maine Medical Center is a winner as Anthem must devise new plan for many policyholders.The state's top insurance regulator was right to decide that Anthem Blue Cross and Blue Shield should allow current customers to keep receiving care at Central Maine Medical Center in Lewiston and five other hospitals in Maine, a spokesman for the hospital said Monday. Superintendent of Insurance Eric Cioppa made his decision Friday in response to a proposed insurance-plan restructuring that would have required some Anthem customers in southern and western Maine to change physicians.