Hello,
I have the same problem on 1 PC (Windows 7): the reason is because RAID is not supported, but this is not written on system requirement at all.

On my second PC: was no error message, but the Windows boot time was absolutely horrible after the GrimeFighter "optimization" (more than 10 minutes!). Hopefully, I was able to undo all changes, but definitively I will no more use this software.

Then I asked to get my money back, but my warranty period will finish in a few without any answer to my ticket about this...
Like a lot of person on this forum experienced, all tickets go directly to trash.

I lost all my trust with Avast now.