I believe the Web Shield problems are possibly related to said HTTPS scanning, which I have left enabled and only stopping and restarting the web shield, quicker than disabling and enabling https scanning (as that would still require a stop/start cycle for the web shield to comply with the new settings.

Since this is a beta, I felt it important to test it in XP as they have changed the way that HTTPS scanning is achieved now. No inserting an avast certificate, but using the original cert. Whilst this basic explanation of mine is probably not exactly the way it is done, but I though it should be tested.

And the post is hopefully to draw attention to it and see if it is an XP related issue, in the same way it originally was when introduced (for XP SP3).