Switch your hides so that the humid hide is on the warm side (you don't want a cold, wet gecko). Also raise your warm side temps to 88-90 degrees. You will need to find some calcium to keep in a small dish as well--you can order it online if you can't find any locally. As mentioned, you should make mealworms available at all times so the gecko can eat as needed--what you are feeding now is not enough for an adult. You can feed superworms, but I personally don't like them because they can bite if the gecko doesn't grab them right. It is possible for crickets to pass pinworms onto reptiles, so it is important to get your crickets from a clean source. You can get a fecal done on your leo to make sure it doesn't have any internal parasites at this point.