This version seems to fix everything that was not working in the previous release (it actually separates stems, can read saved templates from previous Studio One versions, shows instrument thumbnails etc.).
If the app doesn't work at first and says it is damaged and cannot open, just open terminal and type "xattr -cr", then type a space, then drag the Studio One 7.app from the Applications folder using Finder to the terminal where you were typing (the path and file name will appear in the command line after the stuff you typed before) and hit enter.