I was hoping for an official reply.
Contact GOG support directly then. The chance of a blue answering you here is small.
I could, but I am sure they have enough on their plate right now, and official doesn't just mean them ... developer must look in here once in a while surely, and you could say they have more power and more interest at stake. A blue passing by might see it too.
I'm in no hurry, and most likely it is just a mistake ... especially as all the other buyers are not complaining.
I have made an attempt to bring it to the attention of the powers-that-be, so done my bit.
I see you said you JUST bought this Good Old Games, quite literally doesn't sell a version without the downloadable content. If you don't want to install it just use a program like Inno Extract to unpack the installer and see what it contains but I guarantee it will have all of the downloadable content.
JUST bought the GOLD version back in September.
And yes, I've not noticed a similar issue before with content, which is why I queried it.
I could do that with Inno, but as no-one here is complaining about missing content, I feel fairly certain all is okay.
However, that mistake, if it is that, should be corrected ... and the situation confirmed officially.
But you know, maybe I am the only one who noticed, and something is missing for all of us. Inno is only going to help me, if I know what it is that might be missing ... and only the devs or GOG would know that.