I have got some errors while using the "Render Menu Option" of the DVD-Lab, but not one like that yet: "-It stops rendering" . Does anybody know what may be going on?

I am trying to re-author a dvd that has chained files with no chapters. I used the smartripper, then the vobedit, then the ifoedit, then the chapterxtrack, and now the dvd-lab pro to add chapthers between those files... Everything was going fine, but know a got this problem