In the bottom left corner of the Steam client there is "Add a Game", from there select "Activate a Product on Steam", from there follow the steps and you'll see where to enter the code. 

What is actually in this Gift DLC though? It's all a bit of a mystery.

Here's a picture of the parts, they are the last in the DLC style.

The wiki has a list of the ship parts in the DLC as well.

Elite Founders will already have these. They are a gift for registering the game with us but you also link your email which will offer some features in the future.

Hi,

I cannot find the Registration Gift DLC ship parts. Steam says this DLC is installed (see the attached picture). When I enter the code in the Steam activation window, I get the message that I already own this product.

What am I doing wrong? Where can I find those ship parts? Can someone help me out, please?

Many thanks.

P.S.: it seems that the "Style" tab in the Design Mode Parts tab in the ship designer is missing (see picture). It is there where those parts are supposed to be found? Why is the "Style" tab missing?

Hey, Rhonin, it worked. You are indeed a wizard.

A huge thank you!

Cheers