Ok, I investigated about the "View posts since last visit" number that seems to be wrong. It works correctly only if you don't stay logged every time on the portal (main) page like I do even if I'm not online (I keep my PC online because I pay a fixed amount per month to my ISP). The system informs you of the new post since last visit so if you stay logged in the number will be the same every time...
The shoutbox in the front page refreshes every 30 seconds keeping an user logged in, so if you really want to see the new message from the last time you were in front of the pc just leave the browser on a different page, for example the forum index.
However I'll try to find how to put the things like there were with the old software....