Remove the claws and tails from the lobsters. The bodies may be used for stock. Boil the claws for 4 minutes and the tails for 3 minutes, until they are just barely cooked with some translucency left in the middle. Remove the claws and tails from the shell, cut the tails into 3 even medallions. Put the 6 medallions and 2 claws in a small saucepan with the buerre blanc Warm the butter in a small saucepan and fold in the crabmeat and chives. Season with salt and pepper.
Arrange 3 medallions on each serving plate, and put a spoonful of the crabmeat in the center. Top with a claw.
Warm the green leek and blood orange sauces separately, and spoon each sauce around the lobster and crab.
Reduce the shallots and white wine until almost dry in small saucepan. Add cream and reduce by half. Whisk in butter. Hold warm;
In a medium saucepan bring the lobster stock to a boil. Stir in the leeks until all are submerged and cook 1 1/2 minutes until tender. Transfer to a blender and add the cubed butter. Blend until the butter is melted. Then add the ice cubes with the blender running. Blend until smooth. Pass through a chinois and season with salt and pepper. Finish cooling in ice bath.
Juice the oranges and pass through a chinois. In a small saucepot, reduce to a syrupy consistency. Hold at room temperature