So, I did what you asked. Uninstalled Group completely (including settings), Rebooted, Reinstalled new download, Rebooted again.
behaviour is still the same. Problem was always there, not after some event.
it simply does not work. Sorry, I cannot continue to try all kinds of possible solutions.
So I will uninstall it again and go back to my previous solution TidyTabs.
But thanks for your help.