I have been using a BD-RE for testing my projects. Whenever Encore is ready to burn to the disk, even I checked 'Automatically erase rewritable disk..." on the Build screen, the program will attempt to erase and later come back with a device not ready error message. I suspect it has a built-in timer which times out before the BD-RE is fully erased. I have to start this process three times, and finally it starts burning.
Is there another way to erase the BD-RE?
Sorry Paddy, this is not a free bit of software and it may not be the best thing for your needs. At the office we use it for burning data discs mostly and making single copies of things. It's actually got quite a few features including simple blu-ray authoring, although that may be an add-on feature.