The attachedpicture shows the Comskip debugwindow
The top part of the window is the timeline of the recording.
Clicking on the timeline will move the preview quickly to the selected position
The text at the left is the help text listing the available command keys
The black and white image in the back is the preview of the mpeg recording at the selected position
The coloured graphs show detailed information about the recording.
From the bottom to the top it shows brightness, sound, non_uniformity, scene change, logo match, aspect ratio and black bar positions.
Through zooming and unzooming of the timeline you can have both a good overview and see on a per frame basis the transitions. The selected position is the transition between two commercials showing that both brightness, sound and non_uniformity are within the blackframe limits (graph color changes to white) and that the aspect ratio does not change.
I hope this helps in understanding why Comskip is (not) able to do its job.