Sauce:
Place shallots and wine in a pot. Gently reduce to 1 ounce. Add lime juice and heavy cream, and reduce until slightly thickened. Add 2 to 4 tablespoons butter at a time, fully incorporating each addition by swirling the pot very often. Do not let the sauce boil.
Move the pot on and off the heat to maintain a very warm temperature. Strain the sauce into another pot. Add the mango. Using a stick blender, purée the sauce until mango is smooth.
Warm the sauce, stir in the lime zest and keep warm until ready to use.

Fish:
Pat the fish dry, allow fish to come to room temperature. Season fish with Creole seasoning, to taste. Sauté fish in oil, over high heat, turning only once and keeping the seasoning a light brown, not black.
To serve, place 2 ounces of sauce on a plate. Place the fish on the sauce.
Warm 1 ounce of the sauce and the crabmeat in a skillet, and mound a small amount of the crabmeat in top of each fillet