As New Canaan businesses continue to reopen and draw more visitors downtown, motorists who violate serious parking regulations such as parking in crosswalks, in front of fire hydrants and in designated disabled spaces will receive tickets, officials say. Yet parking in municipal lots remains free, and those overstaying time limits will receive a “courtesy ticket” that amounts to a warning, according to Parking Manager Stacy Miltenberg. The system is designed to get shoppers, diners and downtown workers accustomed to the reintroduction of parking enforcement, which officials said had been suspended last month. “Nobody should be parking illegally—we are going to do our best to move people along—but if a car is illegally parked and we can’t get it to move, we will be ticketing,” Miltenberg said. The question of when to start enforcing the two-hour time limits on streets such as Main and Elm is fluid, and will depend largely on how quickly downtown re-fills with visitors.