This suggestion, as long as your problem isn't a hardware one, should work.
If it doesn't, and you post back here to advise us, please also answer a couple of questions.
1.) Re your first post - Is the drive you want to write to the same drive as the one read from in the first part of the copy process?
2.) If the answer to 1.) is no, then please advise if the drive otherwise performs normally outside of the DVDFab environment.
I get the impression from your post that the drive read from is the same one you want to write to... Yes? No?