Haven't seen this.
What I did see was after extracting the .exe from the zip file and running it, it seemed to zoom through the installation process with the time remaining counting down quite rapidly.
Then, with 1 second left, it hung there for at least 5 minutes, in fact I left the room to make coffee and make a phone call - when I came back it had finished.
No issues after that, and I didn't have to refresh the DP browser - the new pack was automatically added when loading Sonar.