What do you mean by The Witcher 3 "folder"? BTW yes, I'm using the Galaxy client, and even the options "configurate", and "download extras" after rolling out the "more" option next to the play button in it, are blocked (in the client). And even though they do not show up in my library they still appear in the "orders history" on the website as "owned". I'm really confused by it, I'll appreciate any help.
Okay This is what you need to do in order to download the DLCs and install them manually:
1. Go to your account page
2. Press the Witcher 3 icon or "folder" as I like to call it (See attached picture).
3. After the drop down menu opens select the DLCs, and if you need any patch (See second attached picture).
4. You would download the .exe files and I am sure you can manage from there.
If you need any more help feel free to add me and send me a message if that is more comfortable to you.
I hope I could help,
I do not see those DLC downloads when I click my game button.... =( Any Ideas?