So sorry... I overlooked that specific hyperlink. Having downloaded the correct application now, I ran the DVD Identifier and have the following message:
[09:35:50] Waiting For Drive To Initialize Disc...
[09:35:52] ERROR : Unable To Initialize Disc In Time : Not ready - Medium not present [02/3A/00]
Both blank DVDs I've tried are Memorex brand: one is DVD+RW and the other is DVD+R.