nOk, thanks for all the answers...
Hey, Nobber22, this goes for you: I did it already

You know, I can hardly find time for myself, my girlfriend is very demanding... But now that she started in the university, she keeps busy the whole day, so I can arrive home and do what I like
I didn't get an answer from the shop, so I will try my best reading about the replacement procedures and see if it is worth my precious free time. Anyway, I see most of you wouldn't give a damn about it, so why should I? (hey, I hope this expression is not a strong one...)
Before I comment on the results... I used the c curve with slow response, I hope it is the appropiate one... At least so is stated in the manual. Something curious: they show both c and a curves, and c doesn't have roll-off at low freq... Are they cheating?
Now the results: I can hardly believe it... My speakers are really bad. Well, not really bad, but they are hardly falling into that what is called hifi... One of the front speakers has a different sensibility than the other, causing about 1 dB of difference. I always thought it was my ears, or the room (one side is an open way to the kitchen), but this time I took my time, I measured, and I believed it. I checked the balance, it was right. I checked the distances, were the same. I swapped the speakers and it was on the other side... So it is in the speakers. I used the balance and now it is right.
The front speaker surprised me, because I expected I'd have to lower 1 or 2 dB to get the right matching (same line with the front ones)... But it turned to be the other way around, so it must be less sensitive. But still, I can't understand it. I don't like much these test tones, so I set the front speaker listening to something in plain stereo and switching then to PLII... And I tried to get the voices exactly at the same depth. That meant -2 dB when I did it... But the spl meter with test tones says something different... Very different: +1-2 dB! Actually, 1.5 dB, but my amp goes in steps of 1 dB. It is incredible how precise this tool can be! Anyway, I will listen to some music and check if I am satisfied (didn't have time yet!), if not, my ears have the last word.
And then, the rears. These were easier, and actually same for both. Since I sit almost in the center of the room, and they aren't higher than my ear (they are floorstanders), I had to give them +2 dB. Same as I had.
Finally, I went to the sub. I was always very careful with its output level, because I have heard many times that most of people set it wrong. Well, if the C curve they show without rolloff applies, then it was definately way too high! Like 7-9 dB!
About replacement, they state in the web site that this item is "sofort verfuegbar"... That is, inmediately available... I know I'm showing off, but come on, I can't compete with your english... I don't know if they send abroad, but if you'd like to get one, I can check it.
I intend to measure the freq response of the speakers and sub, using some sine wave generator, I'll let you know as soon as I finish it. I always wondered how deep my sub could go, and what would be the best crossover.