My experience is similar but I’d really like it to work so I can assign some keypads to each feature.
1. The pump status, temperature abs heater seen to always be correct.
2. If I turn on the deck keys from the C4 app, they will indeed turn on (as long as the deck keys are in the off position when I open the C4 app) but if I set my phone down and the app shuts off, the state will be changed back to off when I open the C4 app again. I’ve tried toggling back on and then off to get it to respond but it will not.