1. You do not need the GUI app to start BasiliskII. "Start" in the GUI saves settings and launches BasiliskII. Once settings are saved in the prefs file, BasiliskII can be launched directly.
2. Better use one of the rom files suggested in the setup manual (and change path in the GUI accordingly). The Performa rom works best for most setups.
3. If BasiliskII still quits on launch, try:
- Copy the application (only the BasiliskII app itself) to a different location (like your desktop)
- Trash the original app
- Move the copy back to where the original was.