sorry, i'm not sure what you mean by library? you can add this twine to a public or private collection through the "Add To Collection" button on the top right of its project page (https://polymerdespair.itch.io/in-the-arms-of-the-night), and you should be able to download it directly from the project page as well!
When a game is purchased it ends up in your "My Library" section, It hasn't ended up there despite the money being drawn from my account, and I can't access its downloads. :weary: I was hoping that meant you guys were providing the download through other means, but I guess not? I'll have to message itchio about it.