Thanks for the explanation, Mike_Carpe_Iter. It led me to a solution that works: I deleted the old Carpe Iter Control app (according to Carpe Iter, it is no longer being developed, which I think none of us knew) and installed the new NGH app. Now Kurviger works with the controller and wonder wheel in both general settings and app-specific settings (I use Samsung S25). There is only one drawback: DMD2 app (which I use sometimes alternatively to Kurviger for off-road) that previously worked perfectly with the old Control app no longer work. It does not respond to any commands from the wonder wheel. It just works when mapping buttons from the button control on the right handlebar, similar to how it was our issue with the old Control app on Kurviger. I have not tried other apps yet.
If Carpe Iter developers would like, I live near Prague and can stop by sometime to demonstrate it in person, if it helps 