Dunno, I'd recommend shutting Notification Center off. There's not much reason for it to exist unless you love pop-ups like you get on your iPhone. The only way to really disable that it to enable "DO NOT DISTURB" for the entire day. For example I have it on DO NOT DISTURB from 6:02am until 6:01am the next day. I know this will be a minute I am never at the computer.
Redifer, I find the notification center to be helpful and your comment not to be since it didn't address my question. I use DND when I need peace but otherwise I have set it up so I only get the notifications that I want. Same with my phone.
Lichinho...only one copy installed.
FCPX.guru...I submitted a bug report to apple via feedback.
Tom Wolsky wrote: Do you get double notifications?
I have all notifications turned off for the one instance of FCPX and the default ones on for the other instance so I am only getting the proper notifications. I don't recall seeing double notifications before turning them off for the duplicate.