Bring 13/4 cups water to a boil. Add millet and simmer, covered, 20 minutes, stirring twice. Remove from heat and add spinach to pot. Cover and let stand 5 minutes.
Heat oven to 350 degrees F. Stir 1/2 cup salsa into millet-spinach mixture. Spread centers of tortillas with refried beans, about 1/4 cup for each. Top each with 1/3 cup shredded chicken, 1/3 cup millet mixture and 2 tablespoons cheese.
Fold sides of one tortilla in over filling and then fold bottom edge of tortilla over middle. Continue rolling to enclose filling. Repeat with all tortillas. Place all on a baking sheet and coat with nonstick cooking spray. Bake at 350 degrees F for 15 minutes or until heated through.