Before I did the upgrade I did a full backup of every file I had on the laptop just-in-case. The upgrade itself took about an hour and it looks good so far. The upgrade preserved my settings, but, there are still a few tweaks to go for privacy.
One of the first things I did was to make Cortana an icon on my desktop bar at the bottom, I just don't want it hogging valuable real estate. The second was to make Firefox the default browser as I never use IE (now Edge). My anti-virus (Avast) still runs without issue and no glitches so far.
Over the next few days I will be stress testing the upgrade by playing my favorite on-line game (Old school Runescape), my office suite (LibreOffice), email (Thunderbird) and graphics (GIMP & Irfanview), scanner (older model Epson) and lastly my printers (wired laser & wi-fi inkjet).
True color doesn't work properly. It is Windows 8.1 only. First step is to turn autostart off, then true color off. If you don't do it that way it can't be turned off at start-up.