.. A Very Big Bingo... I sat and stared at the screen for a while and then gave it a quick format... Windows Explorer is now how I always wanted it... It boots up just fine and the BIOS has changed all of the parameters back to how they were before I started this earlier today..! I don't know how that happened, makes saving BIOS Profiles a bit daft when it just goes and loads the profile it thinks you might like... Anyway, thanks to the good people over at Gigabyte, I suppose... I still have a 100MB EFI System Partition at the beginning of each drive but what the hell, what's a 100 MB at 2 o'clock in the morning..?
Thanks fellas, couldn't have done it without you.