For me Cubase was exiting properly from c7.5 to c8. With c8.0.10 hanging on exit started regularly with each exit, but I was able to simply close the error window, and Cubase closed immediately.
Now with c8.0.20 it hangs on exit bad, every time, it stays active in Task Manager, and after closing error window it takes very long until it shuts down in task manager. Basically, after closing Cubase, I have to restart computer, because reboot is much faster than waiting for Cubase to close in task manager.
There was no change in configuration of anything from 8.0.10 to 8.0.20, just the update. Few minutes before no problem, then update and problem. Clearly something is worse with Cubase.
No other daw is hanging on exit on my setup, only Cubase. This inability of Steinberg to fix this after so many years is simply embarrassing. Actually, they should be ashamed of being unable to fix this problem. Very bad.