With this new Cubase 8.5.15 was born, again, the problem of slow zoom. If you use the G or H keys on the keyboard is really slow zoom not afford to work. Everything happens when there are so many tracks.
The only way for this to work properly, is to remove the graphics of the tracks from Cubase preferences, but this of course is absurd, because you can no longer work the audio directly from the sequencer.
I think there is a problem only resolved with an update by Steinberg.
Why Steinberg ago not knowing anything about?
All very sad.