Aloha M,
First I see this is your 2nd post so welcome to the board. 
What do you want Cubase to show you in the Finder?
When it come to the Cubase programme
under normal circumstances the ‘Show in Finder’ command would
just take you to the ‘Applications Folder’ and then hi-light/select (show)
the Cubase app.
Also
if you are asking questions about the ‘Finder’ you
must be a Mac user. Listing your gear in your sig
(hard and software) would be helpful to the rest of us
helping/sharing with you.
{‘-’}