To make the mango sherbet, peel the mangos and slice the flesh off the pit. Puree in a food processor or blender. You should have 1 1/4 cups puree. Juice the orange and pass the juice through a strainer, forcing some of the pulp through as well. You should have a little less than 1/2 cup. Add to the mango puree. Stir in the sugar and flavor, to taste, with vodka and a few drops of lemon juice, if necessary. Pour into a container, cover and chill. Freeze the sherbet according to the instructions for your ice cream maker.
To make the macedoine, measure the sugar and water into a non-reactive saucepan. Peel all the zest from the orange and the lemon in very thin strips, being careful not to cut into the white part of the rind. Add the zest to the syrup in the saucepan. Slice the ginger and add it to the syrup. Bring to a boil, lower the heat, and simmer for 5 minutes. Chill the syrup in the refrigerator.
Peel and section the blood and navel oranges into a bowl and squeeze the juice from the membranes over the segments. Peel, core, and cut the pineapple into small wedges and add to the bowl. Peel and seed the papaya and peel the bananas; cut into 1/2-inch cubes. Slice the kumquats as thin as you can, removing the seeds as you go, and add to the bowl. Cut the passion fruit in half, scoop out the flesh and seeds, and add to the fruit mixture. Add the kiwi, peeled and cut into small dice. You should have 4 cups or so of prepared fruit. Pouring through a strainer, add enough of the chilled syrup to make the mixture soupy. You may not need all of it. Cover and chill thoroughly.
When you are ready to serve the dessert, put a scoop of the sherbet into 4 to 6 soup plates and arrange the fruit around it. Serve immediately.