I would recommend following our GPT White Paper. You may want to check the section for Plan B as you already have your RAID configuration created.
You mentioned that the installation hangs at 0% Copying Files. Have you tried to use different media? You may want to try the installation with a non-EFI configuration to compare results.
I have tried using the White paper, and no result, still stops at copying windows files.
I have been able to install using non gpt/uefi setup, but i need the storage on the drive as it will be used as a hyper-v host/ backup dc.
I have partitioned the drive to be 800gb primary (os) drive and 5tb storage if it helps.
Another thing I noticed, whenever I click to start the copy, the mouse locks up. Not sure if it's relevant or not.
As for installation media, I have tried both 2008 & 2008 r2, on both own cd, and USB, I have also tried via mdt, but no luck so far