Should we start a poll? 
I don't see what a poll would achieve that 47 posts (so far) in this topic hasn't.
You would have to be asking more than a simple question in the poll:
1. is the Behaviour Shield working for you.
2. what OS are you using (especially important for those where it isn't working)
3. if 32/64bit OS version.
Since this forums software doesn't have the ability for multiple/complex questions, a poll won't give all the answers.
It already looks like win7 32&64bit versions is the OS effected from the posts in this topic. That said, I would have though that there would be lots of win7 systems at Avast which would have been showing this issue.