Hey I had one person that had a similar issue, he fixed it by adding execution permissions through the terminal, example command:
chmod +x "[a]/FinalShot 1.2.1.app/Contents/MacOS/Final Shot"
where [a] is the folder the .app is located in
add sudo before the command if it doesn't run:
sudo chmod +x "[a]/FinalShot 1.2.1.app/Contents/MacOS/Final Shot"
Another approach if that one doesn't work:
Use the cd command to navigate to the folder the .app is in
Example: cd Downloads
Then use this command:
chmod +x ./FinalShot\ 1.2.1.app/Contents/MacOS/Final\ Shot
Let me know if this helps you, I don't have a MAC so I'm not sure if these commands are even correct