The Post button in Vizrt Artist allows you to render out your scenes into various formats for use in other programs or as a stand alone movie. When you Post Render in Vizrt Artist, you'll be able to choose what format movie you want to render it out as and also choose what codec you want to use with that format. This video walks you through the whole process of using the post render option, explaining the various formats involved and how to render out a movie with alpha channel included.
Watch how to use the Post Render option.