Why is the launcher forced stoped?

I installed bb manager on my galaxy then the bb services and then the hub and everything works and thanks CRACKBERRY for that but then I installed the launcher and I set it as default then the home screen works but when I click on the application icon it s forced stop,
Does anyone know why?
Thanks

How much Ram is used by the launcher on ya device? How many are running in background? And lastly how much Ram is actually left to open an app?

Blackberry Z30