Earlier quoted context omitted.
These can be run standalone also (atleast on windows not sure about mac though)
I don't understand how you can run standalone. I just installed it on Windows 10. The only executable is the uninstaller. Please correct me if I'm wrong, but it looks like Lightroom (or Photoshop, maybe?) is needed to use the Nik Collection.
If you dig into the folders there are more executables.
They work as Paint Shop Pro add-ins, too.