I am trying to get back into using Cubase now that it has ARA.
Strangely any VST that is open will disappear when the mouse pointer clicks outside the Cubase Pro Project window. The Cubase Pro Project window remains visible and when I click on it the VST’s re-appear.
I have the Xotopad midi controller on the second monitor which is multi-touch. https://feelyoursound.com/xotopad/ . When I touch the keys to play the VST disappears. The VST does not however disappear when I play an external midi keyboard.
On another PC with Cubase 7.5 I did not have this issue.