I updated my 918+ today from the last 6.x version to 7.01 and then to the current 7.1.
After that I installed the DSM 7 package via roononnas.org.
The installation went through without a hitch.
But the Roon server does not run… when I start this in the package center, it automatically stops immediately.
Did you uninstalled the Roon DSM6 before you installed the Roon DSM7 version? If not please try to uninstall the Roon package now and reinstall the Roon DSM7 version, This might fix the issue.