The only problem I ran into was converting a large vob file. I had two DVD movies that I wanted to place on a single DVDRW for a friend. Dragging the VOB files directly from the disc worked fine, but I didn't want multiple VOB files. So I used CloneDVDMobile, choosing the VOB passthrough option, to create one large VOB file of each movie. ConvertXtoDVD couldn't load the new VOB file. I did discover a workaround, I renamed the file from .vob to .mpg. They then worked fine.