Did you reboot the machine after Avast instal?
Yes, I did (even Avast! tells you to reboot the machine).
See/click the attached below:
Seems your window is missing the options enclosed in the red box. Suggestion: Main window shows option to turn Firewall on or off. I suggest turning it off/reboot, turn it on/reboot. Better?
I will try doing that now.
EDIT: I tried, and look what appeared for a brief moment (see screenshot).
Unfortunately, it only appeared when I connected in a network, after that it will just stay at zero (tried opening different programs and website, but no success).