@ono, Thanks for your question. One of our main goals was to maintain compatibility with Qt user code. We have worked with a significant number of projects who migrated to CS and no one lost functionality. Most code will work without any modifications.
We have a parser (PepperMill) which you run one time to convert anything in your header files which used moc. For example, we change Q_OBJECT to CS_OBJECT(class_name).