I'm having the same problem. I just bought the complete edition, so the launcher is trying to update to the current patch, but a lot of the times, it gives me the "Unable to download patch files" between 1.98% and 22%. What gives?

I'm running on windows 10 and I'm doing it via wireless.

This happened before when I downloaded the free trial. It took me several attempts, but it downloaded eventually. Where's the fix?