You're not alone! Stranger yet... While you have a Mac, I have Windows 10. That seems to rule out an operating system issue. It's almost as though the installer is causing some permanent breakage that gets left somewhere in the system. I say this because I have installed/uninstalled/reinstalled many times the newer 4.5 version, then even gone back and tried to install my older 3.5 Studio One... again, uninstalling and reinstalling... but nothing works. Just like what happens to you, right after either version 3.5 or the newer version 4.5 load all the plugins and midi, the program just crashes by disappearing lightening fast! WTF...
