Hi everybody,
I have experienced also intempestive crashes of KStars since a few months and I reported it.
The crashes occurred especially while running the simulators.
I think I finally found the culprit : kstarsrc
This file kstarsrc is located (on a Mac) at Library / Preferences / kstarsrc. It contains all the user preferences.
I deleted this file and I've got no crash since in the simulators profile or the real profiles.
I recommend not to delete immediately this file but saving it by changing its name.
When you will start KStars again, the Startup Wizard will open and will recreate a new kstarsrc file.