Ego-exo4d Eye Gaze usage

Hi, I am trying to use the gaze data reading from the gaze CSV files. It seems that 1) some takes have personalized eye gaze and some do not, and 2) the gaze CSV files do not cover all the video frames in some cases. So, what is the difference between the personalized eye gaze and the general eye gaze? Plus, is the eye gaze filed in the same fps as the video? Any information you can give about using the gaze data will be valuable.
Best regards.