It is fairly easy.
Do a full backup both databases, just to be on the safe side.
Open the DVD database. Then goto --> File --> Restore database, and browse to the Blu-ray backup file.
Select the following options:
Restore Specific Profiles
under the profile list: Select All
Deselect the following option:
Restore full user database.
This should do the trick. You will probably end up with duplicate collection numbers.
You can solve this by going to --> collection --> reassign collection numbers |