SURPRISE !!
I have a restart problem involving name and password, so do not restart too often unless forced to. Eventually I will attend to this problem, but at present cannot take a risk of being locked out.
I had to restart for a program update and when the computer was live again, the Avast shortcut now produces a panel and everything is back to normal again - Avast panel now shows up and there is no longer a problem.
Thank you all for your kind comments, much appreciated.