In a medium saucepan, melt 3 tablespoons of butter over medium heat. Whisk in the flour and cook for 1 minute, then whisk in the milk and cream and heat through, about 10 minutes. Lower the heat and stir in the sherry, paprika and nutmeg; season with salt and pepper. Cook, stirring, until thick enough to coat the back of a spoon, about 15 minutes.
Pre-heat the broiler.
Season the scallops, shrimp and crab with salt and pepper. Season the crab with the Old Bay. In a large nonstick skillet, heat the EVOO, one turn of the pan, over high heat. Add the scallops and cook, turning once, until browned on each side, 4-6 minutes; transfer to a plate. Add the shrimp to the skillet and cook for 3 minutes on each side. Add the crab for the last 3 minutes of cooking and heat through. Return the scallops to the pan, pour the sauce evenly over the seafood and remove from the heat.
Arrange the bread on a baking sheet and toast in the broiler on each side, then spread with the remaining 2 tablespoons butter. Halve each piece of toast to make triangles. Place four toast triangles on each of four dinner plates, spoon the seafood Newburg on top and sprinkle with the chives and almonds.