Finely chop 1/4 cup cranberries. In a large bowl, combine ricotta cheese, flour, Parmesan cheese, egg, 1/2 teaspoon salt and chopped cranberries; mix until blended. On a lightly floured surface, knead 10-12 times, forming a soft dough. Cover and let rest for 10 minutes.
Divide dough into 4 portions. On a floured surface, roll each portion into a 3/4-in.-thick rope; cut into 3/4-in. pieces. Press and roll each piece with a lightly floured fork.
In a Dutch oven, bring 4 qt. water to a boil. Cook gnocchi in batches 30-60 seconds or until they float. Remove with a slotted spoon; keep warm.
In a large heavy saucepan, cook butter over medium heat 5 minutes. Add sage; cook 3-5 minutes longer or until butter is golden brown, stirring occasionally. Stir in walnuts, white pepper, and the remaining cranberries and salt. Add gnocchi; stir gently to coat.