I called DT and asked for a block diagram of the system. They couldn't provide me with any simplified or detail schematics so I asked for simple instructions. I was able to get the system working using the latest faxed instructions from DT but half the time the Harmony remote would go stupid and I would need to press help and answer the questions to get it to work again. I've decided to forget the A/V and smart boxes. I finally have it so I turn on the TV with the satellite remote and use just that one remote for channel and volume. I really don't want all the fancy stuff, I just want to watch TV without a hassle.
I believe in the KISS principle. Too bad DT doesn't.