Then you aren't vulnerable to the exploit, that however doesn't stop these speculative attacks and believe me they are always going on, it it just that your firewall normally blocks them, so you are normally unaware of them.
Having uninstalled Outpost, now you are seeing the avast network shield take up some of the slack, but it isn't a full firewall (not even close), so you need an active firewall and preferably one like outpost that provides outbound protection. I have never had problems with downloads with Outpost Firewall Pro and I have been using Outpost in one version or another for over 6 years.
If you having uninstalled Outpost, did you not enable the windows firewall as that too should protect against this ?