Timboli: You can put multiple games in your cart and purchase all with one click.
I did that about an hour ago for 8 games at once.
Once your purchase goes through, the cart is cleared.
You cannot put a game in your cart if you already own it, unless you use the GIFT option.
If you put a DLC in your cart that belongs to a game you don't own, then in the huge majority of cases, that will cause the PAY button to be grayed out, and you should also get a warning displayed.
Browse to either game page, to see if you own each game. The GIFT button should be prominent for each game you own.
I advise using your browser to check your library when having an issue, rather than Galaxy.
Well, for some reason, my cart didn't clear; it's still showing both games, and there is no DLC in my cart for a game I don't own on GOG. In fact, the only two items in my cart are those two games. Also, the "Buy as a gift" button is only prominent on the first game (under which is a "Go to my library") button. This is not the case for KotOR 2.
And yes, I've been using the browser for all of this.
Tony650: I think you're getting it right, yes. But if I purchased KotOR 2 then where is it? Both KotOR and KotOR 2 are showing in my cart but KotOR is marked as "Owned" and the thumbnail is semi-transparent, whereas KotOR 2 is neither. Is it possible that removing KotOR from my cart will fix the problem?
Grargar: If you visit the page below:
https://www.gog.com/en/account/settings/orders does it only show the first KotOR? If it does, does the price mentioned match the price your payment method was charged?
Yes, it only shows KotOR.