After 6 more hours of trying everything, Cubase is working again:
The winning combination was complete uninstall, reinstall from scratch, ROLL BACK my UR44 drivers to the spring 2017 version.
After 6 more hours of trying everything, Cubase is working again:
The winning combination was complete uninstall, reinstall from scratch, ROLL BACK my UR44 drivers to the spring 2017 version.