COOKIE DAY N NIGHT gets a pace to stalk and pounce in Sunday’s Omar Walker Trophy at five and a half furlongs after being used up and run off his legs from the one hole at seven and a half furlongs late January. A sprint for horses who have never won an overnight allowance, the feature further restricts foreigners, the conditions writers’ latest attempt to level the playing field, shielding local-bred runners from importees.