Does someone know how to check the services are really up and running, even though the UI says otherwise?
Maybe posting a guideline (in the other thread, which is still pretty short at the moment) helps calm down the panic. 
Click Windows Start => in
search field type
services.msc then
enter. Scroll down to each Avast listed service =>
right mouse click each
service to check if you have the option to STOP.
If that's the case, the services are supposedly running.
Also on the right pane, check the 3rd column
Status (by default it should be
Automatic or Started for each service. If stopped right click and select start). Don't trust this column explicitly.
Right click - properties to check full status on a specific service.
I just stopped then restarted all Avast services again to get back online after these issues started (although the GUI is still messed up.). According the sticky, Avast services are, supposedly, still running in the background.