marklaur: Just purchased the game, the added the Hi Res textures to my account, but they are not showing up in my library.

If I try to buy the free add-on again I get the message buy as gift or go to library.
Has waited awhile but no showing. Games sorted by purchase date.

Am I missing something, on where to find the textures?

Any help will be appreciated, been looking forward to this coming to GoG

terohth: From Galaxy's Fallout4 page, choose 'Extras' tab. Texture pack should be visible there.

Imarion: Will not help, but still I share my experience, which went smotthly.
I bought and installed the main game, originally thinking that was enough, in other words : that the texture pack would be added in the process.
I think thanks to your post, I realised I had to "buy" the texture pack (it is free but we must go through the purchase process).
Then Galaxy started to install them automatically.

As a side note : it won't show in the library, but you need to click on Fallout 4 entry and you will see the texture pack there.