This dialog imports the AVI file and allows you to grab the frame to represent video on the screen if this is not playing - the Still Image.
Just play or skip to the frame you would like to use as a still image and press OK.
When video is playing it will always play on the top of all objects.
Note: To run video by cliciking on some object you have to go to that object properties, click on "Interaction with other objects" button and select Action 1 - Video Play and in the Object select this video object Label.
To run video automatically on the Page Start, open Page Properties and in the Script write VideoPlay("Video1") where the Video1 is the Label of this video object.