If you're still getting the "Do you want the application “Vienna Ensemble Pro Server (64-bit).app” to accept incoming network connections?" when opening VEP and you want to get rid of it, I have a solution.
There have been posts before but I didn't see where everyone seemed to take note of it.
If this is still as issue let me know and I'll post the answer. (I just want to be carefull because it involves replacing the exsisting (code) signature for the Application Firewall. It's not a big deal. It worked perfectly for me. I no longer get that message and VEP works fine.
Steve
Regards, Steve Steele https://www.stevesteele.com