Env - 7.2.1 Mac, ZCS 6.0.10 Ubuntu.
As the subject suggests, when I read a mail in ZD and it is subsequently marked as read, the web view does not reflect this, the same message there is still unread. Everything else seems to be syncronising ok, ie the messages appear as they should. There is no problem in the other direction, if I mark a message as read in the web interface ZD is updated correctly.
I've tried the obvious things, clicking Send/Recieve on both interfaces with no effect. The account is confgured as a Zimbra account in ZD.