Heat a large nonstick skillet or sauté pan over medium-high heat.
Add onion, cider, and vinegar and simmer 30 minutes until onions are tender.
Meanwhile, combine ½ cup flour, salt, celery seeds, salt, paprika, and pepper, stirring with a whisk.
Coat rabbit pieces with seasoned flour.
Preheat a heavy skillet over medium-high heat and melt 1 T butter in a pan.
Brown rabbit pieces well on all sides.
Place rabbit in casserole dish.
Add green pepper and garlic powder to remaining butter in skillet and sauté until tender.
Add onion mixture to rabbit in casserole, then add green pepper mixture and olives.
Cover and bake for about 40 minutes, or until rabbit is tender.
Remove rabbit to a warm platter.
Combine 3 T flour with 1-2 T cold water, stirring with a whisk. Whisk into juices remaining in casserole, then pour into skillet and cook, stirring for about 5 minutes until mixture achieves sauce-like consistency.