Cook rice as per normal in a rice cooker (or stove if that's your usual.) This will take about 40 minutes in a rice cooker. (Note that the pumpkin only requires 10 minutes or so of boiling to be cooked FYI so don't start boiling just yet.)
At the same time, rinse then soak your dried scallops in ½ Cup of hot water to soften (covered.) Don't wash off all the white powder you see on the scallops- these are usually the "umami" bits!
If using fish- optional as I've tested without it and the porridge is still very tasty- marinate them now in the sugar, light soy sauce, salt and cornflour. After marinating for 30 minutes (in the fridge), slice the fish thinly and set aside if not using yet.
15-20 minutes before you want to serve your meal, bring a pot of chicken stock to the boil. Add the pumpkin cubes and dried scallops, along with the soaking water. (If your pumpkin has already been steamed or microwaved, lower to a simmer before adding the pumpkin and stirring till well-mixed.) Boil for about 10 minutes or till the pumpkin is soft enough to pierce with a fork.
Lower the heat to a simmer and, if using, add the fish now to poach till cooked. If not using fish, add the same quantity of soy sauce and sugar to the porridge (as per the marinade.)
Add the shaoxing wine and cooked rice. Stir, taste and season with salt if necessary. (If you are using unsalted homemade chicken stock, salting is crucial here.)