The behavior that you encounter can be caused by an internal error of the application. According to information found on the Internet, the developer of Filmgate has introduced in the version 7 of the product the TVI Calibration Module which will help you fix any similar problems. To overcome your problem, I strongly suggest that you download and use the latest version of the program. To obtain a download link for FilmGate, use Google because the developer's website is unreachable.
