Combine cornstarch, cinnamon and salt in a small saucepan. Stir in orange juice and cranberry sauce. Cook over medium heat, stirring, until thickened. Set aside.
Place pork roast in a shallow roasting pan and cover with about half of the cranberry mixture. Insert a meat thermometer. Roast for 1 to 1 1/2 hours, basting occasionally with the remaining sauce. Meat is done when thermometer reads 160 degrees fahrenheit.
Remove meat from oven and allow to rest for 10 minutes before carving.