Problems overburning with Nero

I'm trying to burn a 654MB video file to a 74min CD-R but Nero (version 5.5.6.4) keeps telling me there's not enough space to burn the compilation to the medium. I have DAO enabled, overburning enabled, and the latest firmware for my Matsu****a CW-7586 burner but the stupid program keeps ejecting the CD (with the aforementioned error message) and won't let me overburn!!! plz help!!!