Uwe,
The System plugin has to be enabled for all of our functionality. If you don't want to use the authentication features, you don't need to set any of the API/Secret keys for each extension. In that case, the login buttons won't be displayed.
I don't think that will fix your underlying issue which I just responded to in your other post though:
www.sourcecoast.com/forums/jfbconnect/jf...gin-processes#p51370
We'll gladly keep helping with that post to see if we can get you going, with authentication, if that's what you'd prefer.
Thanks,
Alex