I don't think they are bugs - but rather issues caused by other software.
Namely, the first one is most likely caused by 3rd party firewalls. The firewall finds out that the executable accessing the network (in this case, avast! service) has changed - and it would like to ask the user whether to permit or block the access. However, since the avast! service is started rather early during windows boot, there is nobody to ask (the user hasn't logged on yet). So, the firewall just decides to block the access. And, since since all the web traffic is routed through the service (WebShield)... web browsing is blocked in effect. But, it has nothing to do with avast! code itself - just with the fact that the executable has changed, i.e. it can happen during any avast! update, no matter what was changed in the code (if anything).
The usual solution is to remove the existing rule(s) from the firewall, and let them be created again.