First, the fact that your programmed action does not work in homekit, but does work in paperUI sounds like a problem with the homekit transport to me. Maybe you can help debugging it with some logs. I won’t be much of a help there though.
Secondly, there might be a way for me to simulate percentages in the binding by coding some logic in the binding to start and stop at certain intervals. I expect this will be approximate as openHAB is not a realtime system, but probably good enough. I would need to get the total time to open/close from somewhere and do a calculation with current position and target position.
To get an idea if I can extract it from the binding communication, I would need some debug logs from the binding. I am specifically interested in:
- startup of the binding (is the time to fully open/close encoded somewhere?)
- log when you stop a rollershutter from paperUI midway (I want to see the NHC feeback on the position)
- log when you try to set a percentage position from openHAB (what does my current assumption result in?)
Can you identify one rollershutter and indicate the total opening/closing time for it?
If I code something, it will require full testing, something I cannot do myself as I don’t have rollershutters. So be prepared to spend some time testing and giving feedback.