You are recommended to go through the entire tutorial at least once before getting into action. That will help you have to a decent understand of the process of developing a VideoWiki script, and eventually rendering the video with the help of VideoWiki. There are several aspects of syntax that important to be taken care of, which would otherwise break the script and fail the video rendering process.
Keep saving the article i.e. hit "Publish changes" button after you have added a some content or media. This will prevent loss of session data in case of any unforeseen technical interruptions.