One problem I ran into with 4.5.0.x is that whenever I would go into BB Messenger after installing an app with DM, it would complain that I got a new device and it wanted to send everyone in my contact list my updated PIN. Of course, nothing changed, and BB Messenger would not work properly after that.

The problem was remedied by placing the 4.3 version of BB Messenger into the 4.5 directory, and it's been running smoothly since.