Bring broth and 1/4 teaspoon salt to a boil in a medium saucepan. Add wild rice and barley. Cover, reduce heat, and simmer 45 minutes or until liquid is absorbed. Let stand 15 minutes; fluff with a fork.
Melt butter in a large nonstick skillet coated with cooking spray over medium heat.
Add leek, celery, remaining 1/4 teaspoon salt, pepper, and sage; cook 10 minutes or until tender, stirring occasionally.
Add garlic; cook 1 minute.
Stir in cooked rice, cranberries, and walnuts; cook until thoroughly heated.