Well, more or less that's what happened:
First I went to a local Nokia Care. The guy was even surprised to see the N9 (he seemed to like it). He told me the system was unable to generate a budget for a repair on a product not sold in Spain, because he was very unsure that warranty could cover an aesthetic damage. So, no warranties on the warranty. He told me that returning the product to the shop was the only choice.
I called the shop this morning and told me they were unable to return the phone to Nokia, because they don't directly work with them, only through a supplier. They gave me the number of Nokia Care Spain.
I called Nokia, and they told me that since the product wasn't available on Spain, there was no warranty at all (that's ridiculous, and I know it's not true, because of course I bought it through a spanish retailer). They told me that there were no pieces, and that repairing it would mean sending it abroad, and maybe was more expensive than a new phone. They also pointed me to the shop, because the customer is supposed to have 7 to 14 days to return the product.
Since the shop has this 7-day return policy, I called them again this afternoon, and they told me that it was impossible that the phone could be damaged because it's boxed and the box is sealed. They of course pushed hard to convince me that they could no nothing at all. They finally said that they would send the phone to Nokia Care, but that they don't know if the warranty would cover it, so maybe I have to pay for the repair.
So in conclusion:
If I send the phone to be repaired, it could be weeks of fighting and suffering for the whole thing, and I don't know if I would end up paying anyway.
Luckily, the scratches are small, and hard to notice, so all the suffering of the whole process it isn't worth it. I will keep the phone as it is.
Since the N9 packaging has the phone on the top of the box, maybe somebody handled it imporperly, and put too much weight in top of it, or hit the box accidentally. Since the N9 screen is curved outwards, it might me more sensitive to this.
Maybe I did the scratch without noticing (I doubt it very much, never had a scratch on a phone, not even in phones that fell on the street, so much less on a phone that means so much to me, and that is brand new), or maybe on saturday, when I handed over to a friend to show her Angry Birds, he hit the screen with a ring or something like that.
It sucks a lot wanting something that much, and be as passionate as I am. I've been loving KDE and Debian since years, and I've felt like an outcast for using this technologies all this time. The N9 was the dream of seeing something you like succeeding, and becoming mainstream. That dream was broken on the famous Elopocalypse, exactly 9 months ago. The N9 meant to me a life saver that I could hang on till I see the land, and I wanted it to last intact for a long time. This probably will teach me that dreams are nice, but you have to stick to reality.
Well, sorry for my rant. I needed to vent a (not so) little bit.