Hi Francisco,
you need to deliver a DDP-Image for (not only) DL-DVD-Replication. this could be done in two ways:
1. DLT-tape
for every layer of your disk a DLT-tape will be written, so the replicator could get every single layers information.
2. DDP-Image on DVD-R (DVD-5)
you need to create a DDP-image using appropiate software like DVD AfterEdit ME (Mac) or Gearmaster Pro (PC). It will create two folders (layer0 and layer1) with the entire information for the two DVD-layers.
if you create a DL-DVD your DVD need to have a valid layerbreak-position. DVD AfterEdit could show you the Nav-Pack, where a layerbreak could be possible if the disk haven´t got a valid layerbreak. I don´t know exactly how you can create it with gearmaster pro as I´m a mac-user, but I know it´s possible, too.
if you finally have created your DDP-image you need to burn the layer 0 and layer 1 folder on a DVD-R (4.7GB). the disk-format needs to be UDF (DVD-ROM) and you should do a backup-copies for the replication, too. this is for security-reason if they might have a problem to read out the data from the disk.
that mean you need to burn 2 x Layer 0, and 2 x Layer 1, and the disks needs be labeled properly.
so you´ll get a replicated DVD-DL.
cheers
danny