In a small pot, bring the carrot juice, oil and cumin to a boil. Remove from the heat and add the couscous. Cover and let sit for 5 minutes. Fluff the couscous with a fork. Season with salt and pepper. Set aside.
In a large bowl, whisk together all of the ingredients.
Place a barbecue wok on the grill. Preheat the grill, setting the burners to high. Oil the grate beside the wok.
In another bowl, combine the octopus, zucchini, onion and oil. Season with salt and pepper. Grill the vegetables in the wok for 5 minutes or until cooked and nicely browned, stirring regularly. Add the artichokes to the wok of vegetables and mix well. Transfer the vegetables to the bowl of dressing. Add the parsley and adjust the seasoning. At the same time, grill the octopus directly on the oiled grate beside the wok for 2 minutes or until nicely browned. Set the octopus aside on a plate. Cut the tentacles into 1-inch (2.5 cm) pieces.
In a serving dish, make a bed of couscous. Place the vegetables at the centre. Top with the octopus and drizzle with vinaigrette.