It is free, yet I can't add it to my collection. Why?

Do you already have a GOG account ? If yes, just claim it on the frontpage and it will be added to your library automatically.

I'd first check to see if you don't already own it.

Beyond that I'm not sure. I think it tries by default to add to your library, and if you have it already then you're gifted a certificate/key.

I got no email for the LBA2 'purchase', but it showed up in my order history (as gift key because I already owned it).

Most obvious: Did you CLAIM it?

It is not really free, you have too hit this field on the main page were it says claim. It shall then change to claimed. At least for me it is at the bottom of the sales.
If you have done this, it
a. shall show up in your library
b. you shall (depending on your setup) receive an order confirmation via email.

If he doesn't, I'm slightly concerned as to how he managed to make this thread.
...there aren't any ghosts in the forum, right? ....Right?


WHAT WAS THAT?!

Maybe an anomaly in the spacetime continuum ?

LBA2 was free to claim (on the home page) only for the first 48hrs of the sale. Did you claim it within that time window?

I claimed it when the banner was on the main page and the text changed to "claimed" but I didn't receive any emails and the game is not in my library or order history.
I didn't see any timers or anything either saying it was limited time.

As mentioned before 48 hour thing. But if you did not receive email and/or it did not show in your history I suggest you wait a wee bit more and/or contact supply. Sometimes they have a bit problems, but quite often it just takes a bit of time.

IF you have again this problem, you shall mention it earlier as even a post in the forum is normally OK for GOG as a kind of proof.

If you missed the official offer, you can still ask for it in this thread:
https://www.gog.com/forum/general/fall_sall_2016_clearinghouse_thread

I'm sure somebody has got a spare code and is willing to gift it to you.