Plutonium

When trying to run the launcher and clicking on T6 multiplayer I get the following error

Yeah... idk why the image uploader is not working, but the error is
"Could not authenticate to Plutonium: unkown error"

Is it truly necessary to save the game in Drive (C:) - Games?

I would like to save my game in another drive since C:\ is reserved for Windows. Can I just make a Games folder in my other drive instead?