Hi Leontis,
Just looked it up on Nero's website and the details for that site are as follows:
www.nero.com
Go to the General info page on the left panel and click on Sitemap. There you click on Support and then HOW TO and a page will come up with How To Guides.
Click on the InCD box and go from there.

I've got Nero myself and have the settings done so that I can use the CD-R as a big floppy and can add or delete as needed. 
Is it possible that you have ticked the box that says "read only" when you "format" the cd before you start the writing session? If so, make sure you have that unchecked.

Good luck,
Martha Shade

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