There is always a huge bunch of warnings and errors (see also: Difficutly installing Roon 1.7 on Ubuntu 18.04.3 LTS using WineHQ [in this example installation run winetricks alone generated 2.1 MB of log output messages]).
Did you abort the script execution? Maybe you should just let it run until completion and see if it terminates with an error code or not (Note: the installation of all the .NET packages can take some time depending on your hardware – go eat something/watch a series episode/watch a movie/listen to an album/… while you wait). Maybe it’s best to delete any unfinished winprefix (’/root/my_roon_instance’) before you try again.
PS: Looks like you’re logged-in as root. Are you sure about this? You should be logged-in as the user that want’s to use the Roon Control later on and run the script with sudo as the installation goes to the current users home directory.