Hi Sven,
As far as I know the etc/org.apache.karaf.features.cfg is with the hot loading not necessary, only the security settings.
I've added the roles annotation-admin and annotate manually to one published event.
Did you adjust the listproviders?
Maybe you should check the webdevoloper output. One of mine errors was a missing setting for the mariaDB in the custom.properties (The MySQL Metadata).
Regards
Stephan