I had an even funnier issue with this, an issue you ask? Yeah, I own it, and could click on the banner to get it.. and it claimed properly with site saying "added to library" I got it.. except I got.. a gift certificate? from a friend named.. you guessed it, ME. Wut? (To repeat: I owned it and was just curious why it said I could claim it)

So.. ehm. . yay?

This is normal.
Since if you already own the game you get a gift code that you can send to someone else, sure you can't redeem the game twice though.
This is how it usually works. Think the key can be redeemed until 6 july, so when the giveaway ends i am just gonna give it away to someone or the gog community giveaway thread.

Though the game is DRM-Free then I am not sure that it's legal to install it on two computers for LAN MP play if you have only one copy (I believe that GOG for the same reason gives a key for MP play for the games that needs it...
So if you want to have LAN MP play with a game then it is possible that you would still need two separate copies of a game . So in reality you could make a second GOG account and claim the second copy for your own use if needed to get a second key for games that needs it for MP...
I do not know if Total Annihilation: Commander Pack even needs a game key put in to support LAN MP , I am just informing you of what you can also use a second game for in principle....

It's been so long time since I tried to get up to date on rules and regulation on GOG and I simply can not be bothered to have to go through all the 'key' answers on the support pages to find out now , bit if the above is in-correct then maybe someone will correct me ;-) :-D

I also bought the game (both games, actually) in May 2011. It was on sale at the time (50% off). Probably weekend sale. So perhaps that had helped your decision.

Might? Too bad there's no global network of computers to look up such information.

Seems i already have the game :D
Anyway, seems i have many games i haven't played yet :D

Why bother when we have skilled and knowledgeable people like you around to do that for us...

But FYI then my reason for expressing myself the way I did were because I couldn't remember the chronology of it all , e.g. how far the C&C franchise had gotten when the TA game and it's expansions came out..
What I do remember is that I thought TA as one of the best RTS games of that time (I only got it in 2011 from GOG and while I think that I had main game on disc already and were mostly looking for the expansions in 2011 then I also remember how I a lot earlier found TA impressive compared to it's 'peers'....
There is a review by a user with handle 'n8mahr' over at the page : https://www.gog.com/game/total_anihilation_commander_pack
It's titled : Shunned by the press, loved by gamers! , go and read that if you want (# 5 from top on my page)
Review above from 'Blarg' claims that 'it was 3D when games were still using sprites, including Starcraft. '
And so on and so on....
Anyway , I would rather have you take your fine discussions with someone else on the internet rather than I have to read a lot and reasearch more just to satisfy you. In an emergency then go satisfy yourself ...

P.S.
My use of the word 'might' were also other than what you suggests , my use were like if I had written that while there were other games then..... (there might have been other RTS games but)
Thank you :-)
You must have gotten the game cheaper than I my receipt from May 6 , 2011 says :
Total Annihilation: Commander Pack $5.99
order total: $4.19
Which as far as my math abilities goes is only %30 off

Anyway , I have no regrets about the price , it was money well spent :-) (Thanks at GOG for that)(Great game)

On this topic, this is quite a piece. According to it, "Herzog Zwei is usually hailed as the first RTS. It’s certainly the earliest that still looks recognisable today, and it’s responsible for a multitude of mainstays. Released for SEGA’s Mega Drive in 1989" but "Herzog Zwei may have kickstarted the RTS, but it was Westwood Studios’ Dune II, three years later, that popularised it." and "’99 still had some tricks left, not least of which was Homeworld. Relic’s hauntingly beautiful space RTS was the first truly-3D strategy game." (So it doesn't consider TA as true 3D, just lists it as having 3D terrain.)

Thanks ,
As far as I know I didn't write that TA were the first only that I think it the best RTS for it's time...
also I do not think that I wrote it to be 3D , I only quoted someone else , but for arguments sake then I am sure that some would say a game is 3D if it has 3D terrain....

P.S. / By the way
I really think that the article should have mentioned "The Tone Rebellion" , ref. : https://en.wikipedia.org/wiki/The_Tone_Rebellion
It's listed as a pseudo-3D real-time strategy game only but still a great game..
Also the article does not mention Dominion: Storm Over Gift 3, which is another at least nice game , that I think deserves to be mentioned in the history of RTS games (both games are from late nineteen-nineties )

Thx, i love this game a lot, played this game a lot with Aqua music that was all the rage at that time.

What I can say, LifeLover - you are right for 99,9%, When you have problem(s) with some functionality in store, WHERE you spend your money - you are counting on help of team of this store!!! If team dont want to help with solving this problem - YOU DON'T WANT TO SPEND OWN MONEY in this store!!! This is how it works! YES!