Sorry, perhaps my english is not enough:

(I tried in your demo too, there was even no cb articles tab

In my eyes it shold work like in cb blog: you create a blog and save it, then the notice about a created blog is shown in cb activity (mod and tab). The blog is shown in cb blogs tab

If I create an article (in Backend or Frontend) and save it. With the enabled settings (see above) there should be shown a notice about a created article in cb activity (mod and tab). But the article is only shown in cb articles tab, there is no notice in activity (even with the above settings).

That seems to be a bug (which is in your demo too!). And it looks like to be the same bug like 6 months ago in posts of alex76

Thank you so much for your NOT help! It's always the same here: I need 3-4 times to show you that there's something bad, until you see it.
This is an important info for all other users. If you find problems, insist 3-4 times, then they will understand you. Sorry

I logged in as cbadministrator in the demo and activated cb articles tab, this worked. Then I activated auto actions cbarticles, then I wrote an article and saved. The article was shown in cbarticle tab but not in cbactivity tab.
So it seems, the demo.joomlapolis is bad configurated like mine.

I am now for years here as professional member. But I am treated like a newbie.

Thank you, this was helpful: for some reasons, I don't know wha the system plugin was disabled.
After enabling it works like I want.