Hi Liggy,

First of all, thank you for responding, I am Honnored

Ok, now I understand the difference between the 1.** and the 2.** firmware.
Since it is more understandable to call it "master" and "Slave", I understand that the 1.** is the Master-firmware and the 2.** is the Slave-Firmware

I can now imagin that since I changed my Nec ND-6650A from Master to Slave with the tool 6650slave.exe, I can flash the DVDrw with 2.** firmware and not with 1.** firmware
And also the other way around

The trouble is that because the Bios doesn't recognize my DVDrw anymore (because I changed it from Master to Slave), I can't use the tool "6650master.exe" or "NEC ND6650A Master Bootcode Flasher"
My task is now to first make my DVDrw recognizable to the bios before I can change it back to it's original Master setting
After that is done the Bios will recognize my DVDrw again and I should be able to load the 1.** firmware again
I just now ordered a IDE converter for the Slim DVDrw and I have a external USB bay.
I hopefully can use the two together to make the drive recognizable in the BIOS, otherwise I have to find an old desktop

Anyway I understand what went wrong and there is still hope that I haven't completly bricked my DVDrw
I will report my results as soon as I tried it in the comming days.

Your comment about my option of adding a media code to the firmware is understandable.
I am just saying that I want to give that option a try (once my DVDrw is back to it's original state).
With the tools mentioned I already have seen that the Mediacode of my DVD's are not in the firmware, so that was the reason that my DVDrw couldn't burn them.
The next DVD's I buy will be Verbatim as you recommended.

Thanks so far

A hopefull Digi