I successfully installed this new OS over the older 4.5 version using the bbsak application. Backed-up everything using the Blackberry Desktop Manager and then wiped the memory clean with the app and installed the new OS. Needed to turn-on connection to mobile carrier (Fido - Canadian). but otherwise it works great. Keyboard lock icon is missing but I discovered that holding down "A" is the faster way to do it.
Sadly I lost all my virtual Texas Hold'em dollars so I now need to start at the loser table :P
Still can't figure out how to disable tones while dialling numbers.