installing Studio One 5 Professional - exe

First, I'd ask the developer about this. Implementing options for silent / unattended installation is their (PreSonus, in this case) job and only they can do it. As they provide no documentation on it at all (yes, I googled it too :)), I'm afraid it's simply not available. 

Apparently, according to silent-install.net, Studio 3 supported the /s parameter for its setup.exe. It might be worth a shot. Silent installation aside, I assume the installer will not activate/register/configure the product (as this requires account credentials, apparently). 

If you're lucky, the developer provides some kind of CLI-tool for that... I wouldn't hold my breath though. You next best shot would be to see if the setup stores something about activation in registry (using a tool like Regshot or something) and trying to see if you can clone that.