Passing DLR isn't that hard. If you train well enough with the given material, you'll be fine. 10-14 days of preparation should be enough. Keep an Excel file with your scores and give everything you have. Practice A LOT, but not too much. Otherwise it will be repetition.
For which airline did you do the DLR?
PS:
AFAIK Cargolux does Mollymawk now.