Place curry powder in a large skillet and stir over medium heat until slightly darker in colour (about three minutes). Add chopped apple, onion, lemon juice, mushrooms, broth, and 1.5 cups of the apple juice; bring to a boil.
Add all the remaining ingredients to the skillet.
Rinse chicken and pat dry; add to skillet.
Reduce heat, cover and simmer for 30 to 40 minutes, or until meat near bone is no longer pink; cut to test.
Lift chicken from pan; arrange on a warm platter.
In a 1 cup measure, blend flour with remaining 1/2 cup apple juice.
Gradually add to sauce in pan, stirring; increase heat to high and cook, stirring until sauce is thickened.