Re: trying to figure out where I went wrong and stop if from happenning again
Leon, I am going to assume that you started with a 5 pound package of workers, drones and one queen, and yes pictures are very beneficial to solving mystery's such as yours, it takes some of the guess work out of it. First off I wanted to say that if the plastic parts at the bottom of the hive was warping and you could feel the heat when opening the hive I would guess that your bees were way to hot inside the hive and probably absconded on you, and the hive was robbed, when conditions inside the hive get to be unbearable to the bees they will leave. The next time you set up the hive it might be best to place it in a more shaded area or under some type of small roof and perhaps upper ventilation as well.
The maggots could be from the flies although beetle larvae look similar to fly larvae if you are not familiar with them, your hive may have had more beetles than you were aware of. I am not familiar with dietamaceous earth but I don't think that it would be the cause of your hive absconding.
I am saddened by your loss, as a fellow beekeeper I know the amount of care and time it takes to get your hive as far as you have and it is always disappointing to loose them and your honey crop, keep your chin up there is always next spring which is not that far off.
Bill...in Southeast Ohio Zone 6A, Never look down on anybody unless you are helping them up