Hi Robert, The "#selectedLaunchConfiguration was sent to nil" sounds like an error in Pharo Launcher version 2.0 that several people have seen.
It's corrected by updating Pharo Launcher to version 2.2. You can get it at https://pharo.org/ ; it's not necessary to uninstall 2.0 first, just install 2.2. -Ted -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
