sadthiago: Guys, i got the good news. Firek from gog replied to me and said that the agreement with inxile was to offer for whom bought the upgrade from the standard to deluxe edition another upgrade as courtesy. This upgrade iin question gives the classic stuff that was missing. I already got mine and everything worked smoothly. I Hope that you guys that already bought the upgrade receive that new one as soon as possible, but dont forget to contact gog.
On a side note, I received the answer by doing another contact with gog (after one made more than a week ago), they answered this time in the same day.
MIK0: I was going to report the same things. You have to contact GOG about this issue and they'll give you a redeem code to add the classic edition content (upgrade from standard to classic).
From my discussion with InXile support I got the impression that the issue would've been solved automatically, but that is not the case. I find it a bit unfair, they have the means to know who has both standard and deluxe edition but not the deluxe, they could correct it automatically or contact all the users that meet the requirement.
I noticed that however my ownrership of the game is not correctly reported because both classic and deluxe are not shown as owned by me.
Firek said about this in the reply, as follow "Sadly, due to technical limitations, it's impossible to upgrade the Standard Edition to the Classic Edition via the store. Because of this, those who purchased the Deluxe Edition upgrade were left missing the Classic Edition content, with no way of resolving this with an additional purchase."
So as i understood, it seems that they can't do it by themselves, but they can spare a code for the upgrade to classic edition for the people that bought the upgrade to deluxe edition.