[Mark Weiber]

Thanks for the response.
I still would like know why DVDA miscalculates the final size of data. I’m saying this because yesterday I tried another utility for DVD authoring called TMPGEnc Authoring Works 4 and I did manage to jam in all of the videos. The space they took was as expected, give or take a few MB, with 400MB left unused. So the bitrate calculator was very accurate. Take a look:
https://dvd-hq.info/bitrate_calculator.php?length=283&vformat=PAL&audiobr=192&astreams=1&ratemode=CBR&motion=Heavy&scenedetect=Active&brlimit=9800&discsize=4482&otherassets=400#Calculator