Whisk together the soy sauce, chile sauce and brown sugar in a small bowl.
Place a wok over medium-high heat. When it's hot, add the vegetable oil and margerine. When the margerine is foaming, add the curry powder and onion and cook until the onion softens slightly, 3 minutes. Add the scallions, sencha loose leaves, and garlic and cook another minute. Stir in the rice, and toss until the grains have separated and softened. Toss in the shrimp and stir briefly to heat through.
Drizzle the sauce over, and toss until it coats the rice evenly. Move aside the rice to expose a portion of the bottom of the wok or pan. Add the egg and allow to set, then scramble and chop up to toss into the stir fry. Season the rice to taste with koshur salt, if needed. Have a nice dinner.