When I make a DVD with DVDA 4.5 the colors change a bit and gets darker.
If I put the rendered DVD file on the timeline next to the rendered HDV file using Pro 8, they are identical. But when I make the DVD it turns out with with slight color change and darker. Does anybody have this problem?

What is the source? What player are you using to view the content? Software or hardware?

Spot, After reading your reply, I played the DVD on other players and discovered that the player I normally use connected to a Samsung DLP Wide screen 1080i TV actually plays darker than the other DVD players connected to the same TV. Thank you for your input. By the way, I have several of your Training DVD's that helped me learn Vegas editing.

...the player I normally use connected to a Samsung DLP Wide screen 1080i TV actually plays darker than the other DVD players connected to the same TV.

Bob, my guess is that this particular DVD player isn't adding setup (7.5 IRE) while the other ones are. This would explain why it's darker than the others.
The unfortunate part is that this feature (or lack thereof) is almost never docimented in the player specs :-(