Digital Media Converter's PAL-to-NTSC DVD conversion doesn't output to .VOB files (instead, it outputs to .MPG files, and chapter count/info is lost because a .VOB containing more than one chapter becomes a .MPG with all chapters merged into a single one).

So, I can't use Digital Media Converter to convert a full PAL DVD (from its ripped .VOB files, including menus, additional titles, subtitles, audio tracks, angles, etc) into a "carbon-copy" NTSC DVD because of this chapter-merging problem.
What can I do then?