How can I make PI's stage 720x480 since when I hit Alt+3 it becomes too large.
And when I render AVI for further processing in Premiere Pro 2.0 it is smaller than the 720x480. What am I doing wrong?
What do you mean that it becomes too large? What is your monitor's resolution set to?
Instead of hitting Alt+3, you can always just grab the borders of the Stage window and drag them out to make them larger. Just so long as the stage area is bigger than 720x480 when you hit the render button, you should be fine.