Hi William,
The HitecWeather Deluxe I have works on the same basis as AAG incorporating s two sensors, a high precision Infra-Red (IR) measuring device and a digital temperature sensor. Using this data the level of cloud and be determined and set to specific values. It also has a direct feed that can be wired and trip the relay and close the shutter. I think given the choice I might have gone for the AAG version as this also has the option of a wind detector and a proven link to the Boltwood compatible single-line data file but as this was a prescent from my wife and son so I need to stick with it. HiTecAstro also has its own software but I cannot workl out how tol link this to the Bolwood file. The Boltwood Cloud sensor would cost over $ 2,000 this has a link to Maxim Dl but the price is excessive. They do have a replacement Adapter Box which might be an option but this works on 24 volts However, I noted your comment that AAG software would also work with HitecAstro It might be worth a try before buying ACP
Cheers Nick