The issues I have seen are with people using an older OS. You need to be using OS 4.5.0.131 or newer. Some people using 4.5.0.66 and such have had the BBM icon disappear after installing. You also need to have at least 5MB of free memory, or the app will not install.
There really should be something in the install script to make sure a certain OS version is installed first, but that is not there.
As long as you are running at least 4.5.0.131, you should be good to go.
