Place scallops in a shallow dish or heavy-duty zip-top plastic bag.
Add wine mixture; cover or seal, and chill 30 minutes, turning once.
Soak 6 (12-inch) wooden skewers in warm water 30 minutes.
Drain.
Bring 1/4 cup brown sugar, ketchup, chicken broth, rice vinegar, soy sauce, cornstarch, sesame oil, minced garlic, and, if desired, red pepper to a boil in a saucepan over medium heat, stirring constantly. Boil 1 minute; remove from heat, and set aside.
Remove scallops from marinade, discarding marinade. Thread scallops 1/2 inch apart onto skewers.
Grill, covered with grill lid, over medium heat (300 to 35
to 3 minutes on each side.
Brush scallops with brown sugar sauce, and serve immediately with remaining sauce.
Serve scallops over hot cooked rice with chopped fresh parsley.