blog.zugschlus.de finally got its Impressum. I implemented it as a static page, which can be seen as http://blog.zugschlus.de/pages/impressum.html if one knows the link.
However, it does not show in the side bar in the static pages plugin.
In the static page itself, "publish-status" is set to "publish", and "Include in sidebar-navigation" is set to "Yes."
What do I have to set to make the Impressum show in the side bar?