I consolidated the code base today:
- removed unused functions in the Controller and AppCanvas classes
- corrected a crash when the scene is empty
- removed AppGLWidget and all related classes (AFAIR, this was the last remaining Qt dependency)
- added an AppView class to transfer camera information from Blender to Freestyle
- corrected the Python interpreter so that the executed scripts are not left opened in the text editor
Let me know if the 17784 revision is unstable.