Hello Frank,
- You can only have one version number of Hauptwerk installed on the computer at a time.
- Once v6 is installed you can't go back to using v5 or v4.
- Only one instance of Hauptwerk can be running on any given computer at any given time. You can't have two different Hauptwerk configurations (e.g. 'Hauptwerk (alt confg N' desktop shortcuts) both running simultaneously, for example.