Today I received a boxed version of Cubase 9 Pro.
Installed, started and here what I 
see:
A a little disappointed. 
My system: Windows 7 64bit
Here is an article on using Aero with Cubase:
https://www.steinberg.net/nc/en/support/knowledgebase_new/show_details/kb_show/windows-7-error-message-dwm-composition-is-not-running-please-switch-to-an-aero-theme.html
I hope this information is helpful.