Hey ! Thanks for your logs, it's very interesting since I can't test HDR myself.
In 0.3 Hotscreen don't allow HDR at all. You said "Screen latency to correct delay above 0 will break HDR" and I also suspect that even the detection doesn't work with HDR.
I will try to handle HDR in next updates. It's not hard but I can't be sure that it works when I publish it.