Attachment Download code in UR 7 - an update

I've updated my original post here to reflect a suggested fix posted by Microsoft on the MSDN Forums here.

Despite my major reservations with how the problem arose, credit is due to Microsoft for responding as quickly as I think they possibly could (even if it doesn't always seem that way).

My reservations relate to disagreements on the need for the change made in UR7 (I don't think it increases security at all), and also to how MS allowed a change that broke supported extensions. It'll be interesting to see what happens with UR 8...