Continuity mistake: When the boys are sneaking in to take the pictures of Payne, the first time you see him in bed the clock says it's 4-something. When they come back and get the boy in the dress in the bed, the clock says 12-something.
Continuity mistake: When Major Payne screams while telling the story of the little engine that could, the wide shot shows that his hand is on his chair. The close-up however shows that he's sticking his hand out.
Answer: The credits are in alphabetical order (according to last name). He did get top billing in the opening credits though. Damon is actually listed 25th in the end credits, after his nephew, so I don't know what you saw where he was listed 7th or 8th.
Bishop73
I have the movie, and his name is right after his nephew's, so I guess I got the place wrong.