There are two issues with zd2 b2 on windows 7 x74 that I've noticed. Both have to do with the way the app displays in the toolbar area.
#1 most apps don't create a separate icon for the app when it's running. in windows 7, if I have pinned zd to the toolbar, and I start zd, it's icon should become 'active' looking. Instead, a new, separate zd icon appears.
#2 more important is that the zd tray icon does not seem to show when new email is waiting to be read. With other OS or other zd (not sure which) the red zd icon would turn into a yellow 'letter' icon.
It's too bad that neither of my wished for and written about features have been added to zd 2. that is, copy paste images directly into the body of an html email, and having zd open on the right hand monitor if that's where it ran last time around. Others have requested the same of course.
Otherwise b2 seems pretty well behaved.