Ok Saska,
here is the link to the list of food we 'oldies' tend to follow. It's taken straight from the UK edition of the book, reposted by Maintainer earlier this year.
http://www.minimins.com/dukan-diet/254782-list-dukan-safe-foods-new-people.html
Dairy needs to be Fat free (also called 0% when in fact it is usually 0.1%) and in the pre-Lifeplan edition of the book it does refer to a 'maximum of 1L / 1kg dairy' and only 250ml skimmed milk. If I get the chance to look tonight I'll give you the page number. Other description for dairy as 'low fat' or 'extra low fat' can be very confusing so I would always check the label for the grams of fat per 100gr. If it's more than 1 for dairy then stay clear. Milk also had Carbs in the form of Lactose which is why milk specifically (but not yoghurt etc) is explicitly limited top 250ml. I don't think I ever measured or actively restricted my dairy intake and I had no porblems but I have the feeling that I did not usually reack the 1kglmit. I also had the lowest fat Cottage that *I could find* cheese throughout, and a lot of the times that was 1.2% fat from Saisbury's. These are small details that might slow you down a bit but should not make you fail altogether.
Then there are 'extras' or 'tolerateds' which some people use when they get fed up, like EL Philly (one tablespoon/day) or sugar free jelly (3 portions a day) but to start with you really ought to concentrate on the basics and not be side tracked by the 'treats'. They were never mentioned in 'the original' book but it sounds like they are now, and maybe that's what's causing the confusion? In many cases the exact type and brand matter, for example I don;t thin there is any hard cheese available in the UK that fulfils the less than 7% fat rule to be a tolerated (or whatever it was), of the 'lemon flavoured yoghurt' that was mentioned in the first book, so we all stuck to plain yoghurt.
Good luck - keep it simple, stay away from any prepared or precooked foods and you should be FINE. Think 'no fat no carbs no sugar' that should do the trick when deciding if something is "safe to eat"