That's OK as Avast will protect its own files and registry entries, so you can let that pass
As for windows security centre that is a known problem that we can fix later
1/3 of the updates have installed, so I'll restart when that's complete, I haven't touched Avast at all, it seems fine since I'm using the safezone of course, Formatting of the 1TB hdd, which I wish i didn't pick the long format since that's taking forever, but when they are both complete and I reboot to finish the updates, I'll get back to you.