Even though I mentioned my comfort using Cubase 8.5 Pro on macOS Sierra in this forum, This does NOT mean that you could use the current Cubase 8.5 Pro build on macOS Sierra without any issue. (As I said, I never use its video funcitonalities.) I still suggest you guys to wait until Steinberg official announcements. Once they finished the testing and came up with any usable workaround or solution, they will let the public know.