This is from
http://www.turtlepuddle.org/cuora/caresheet.html
Waxworms? I am not familar with them - but here is the full text.
Feeding: In diet, at least, the Malayan is somewhat like other box turtles--omnivorous. However, aquatic plants provide the main food source for C. amboinensis in the wild. Provide a variety of greens 'n veggies, some fruits, mushrooms and an occasional waxworm or cricket. "Gut loading," or feeding nutritional plant matter to the worms or crickets before offering them to the turtle, improves the quality of this food source. Use a good supplement, formulated for turtles, to assure proper nutrition. (Supplements are not needed daily if the animal is feeding well and is provided with an excellent variety.) Malayans prefer to feed in the water, if the water is warm enough. Aquatic plants and greens can be provided in the pond or aquarium at all times. Feeding in a sink or plastic tub away from the aquarium will make cleaning easier. Healthy, well-nourished turtles do not require large feedings on a daily basis. One or two substantial feedings per week should keep your turtle happy and active without risking overfeeding. It is a good idea to keep cuttlebone, or some other high calcium food, available all the time. (Please note: turtles should not be fed spinach, rhubarb or parsley as these are high in oxalic acids, which can cause calcium deficiency.) There's more diet information at The diet dilemma. Also see my set-up page for more on feeding. A list of good foods for turtles can be found here: What Should I Feed My Turtle?