1. When I try to copy the special k .Dll file over to the installation directory for Xbox app nier installation folder initially it said I didn't have permission. I took ownership of the folder and all sub folders and files. Now when I try to copy it over it says I am out of space but I have 25 GB available. I have verified my user account had full permissions to the folder. What are the installation instructions?
Ah, never take Full Control of the WindowsApps folders -- you're more likely to break something than anything else and even with access to them you'll be unable to manipulate the contents of the game install folder.
Special K can only be injected through global injection, so basically:
1. Install the global injector of Special K.
2. Join the Discord server and download the latest SpecialK.7z and SKIF.exe from the #release channel.
3. Extract the 7z archive and move the SKIF.exe to the Documents\My Mods\SpecialK folder, overwriting existing files in the process.
4. Launch SKIF.exe and open the Options tab. In the Whitelist area, type in NieRAutomataPC and then click on the Save Changes button at the bottom.
5. Next click on the Global Injection tab and click on Start Service to start the global injector.
6. Launch the game. If everything works properly Special K's GUI should appear and you can hit Ctrl+Shift+Backspace to access its in-game control panel.
Also if you play any multiplayer games it's important that you stop the injection service before launching any such game. See this section for more details as to why: The global injector and multiplayer games.
2. If I turn on AA and AO I get a black screen and have to force the app closed. Is this normal? If I have to choose between the two which should I choose?
Just use AO. It includes a post-processing AA filter.