In a heavy saucepan add water, zest, orange juice and salt. Bring to a boil and gradually whisk in the polenta. Cook polenta over moderately low heat (it should barely boil), stirring constantly, until very thick and it pulls from the sides of the pan about 3 minutes. Once cooked evenly pour polenta onto a lightly greased 1/4 sheet pan. Sprinkle with fresh black pepper, cover with plastic wrap and place in the refrigerator until firm about 15 minutes.
In a mixing bowl add the crabmeat, diced figs, zest and juice of a lemon and mayonnaise. Gently mix trying to leave crabmeat in lumps. Season with salt and fresh black pepper, to taste. Cover bowl and place in refrigerator until ready to use.
In a blender place the chives and basil and a little of the oil. Start to blitz the ingredients together adding more oil until the mixture is a smooth green herb oil. Transfer to a squeeze bottle or a bowl and set aside.
Preheat grill to medium-high.
Remove polenta from refrigerator. Take a large can (3-inches in diameter) and remove the top and bottom lid. Using the can cut 4 rounds of polenta. Brush olive oil on both sides and place on grill 3 minutes per side. Once grilled place a polenta round on the center of a plate and use the same can for molding the crabmeat salad. Place the can over the polenta and spoon in about 1 to 2 tablespoons of the crabmeat mixture, push the mixture down with the back of the spoon and lift the can away creating a crabmeat mold on top of the polenta. Top with a few mixed green leaves. Drizzle herb oil over top and serve.