There is a undocumented Flag 'NERO_BURN_FLAG_NO_BOOKTYPE_CHANGE'.
What does it do? When do I need it?

And also: When (what for) do I need 'NERO_BURN_FLAG_BOOKTYPE_DVDROM'?

New NeroBurningRom allows several Booktype settings, but there too, it's not documented.

Please enlighten a dummy!

In addition to above...

is there a way to read the current writing speed i.e. during 'drive_OnProgress'?

Nero itself already can do it.

No, currently there is no way to do this.

I'm still curious about the 'BOOKTYPES'.

Please...

Thaks for proving again, that NERO-Peole are either stupid, negligned or just don't carer!
After more than two month, none of your 'DUMMYS' could explain a 'Booktype'.
Don't bother anymore, I asked a 6 years old school girl.

Edit:
The 6 years old school girl advised me, to use a programm made by professionals, never to be as stupid as to use an unsupported programm like NERO. She recommended 'Pinnacle', they answer!

Your rude comments won't take you far especially in terms of support on this forum. Nobody knows all the answers in the world. I personally answer all queries when I know or suspect I know the answer. If something is left unanswered it does not mean it is unread. Politeness is a priceless virtue that you seem to lack.

As for your original unanswered question, a simple Google search (or any other major search engine of your choice) would have gotten you the answer in about 30 seconds, e.g. http://www.dvdplusrw.org/Article.asp?mid=0&sid=2&aid=42

Rude...
Politeness...
alexp..............

You really don't hesitate to use those words after not answering for more than two month a simple question regarding your product?

And than, after more than two month instead of answering a simple question regarding your product you refer me to Google???
Answers about NERO I get from GOOGLE?

That's poor!
I'm better off beeing rude than poor!

Before this gets too far, I should only tell you that I stand behind my reaction towards you. You were very rude and you know it. I very clearly explained why you did not receive your answer.

I don't have to know answers to all questions, do I? This is not a paid service where you get your support queries answered in 24hrs. We do our best to help everybody. Have you taken the time to read Matze's initial sticky thread? I will quote: "We will also monitor the messages from time to time and try to help where possible."

I only mentioned Google as I personally use it a lot. It gives me superb results 99% of the time. If you tried it, you wouldn't be so angry that no one answered you for 2 monhts. I could have given you the URL I have just given you the very first day but I expected some of the other users a more educated answer. Besides, should I post "I don't know" just to let the other peer know I have read it? That doesn't make sense.

No, you are plain wrong. Being rude as you present yourself here will never get you the expected result, only the opposite. You can be rude as much as you can but it won't be tolerated here. You insulted me personally for no particular reason.

I have nothing further to say on the subjects. Criticism is always welcome and insults will only get you banned.