Rollback RX Install Problem

I am trying to install Rollback. When I get to the point of the actual install it says there is not enough space on HDD. I have about 560 GB free on C drive. I have an HP laptop and it has the HDD split in two with the D drive having about 3 GB free. Is it trying to install to D? I tried a couple of times and got the same results. I tried using default install and custom install and did not see where it was trying to install to. Thanks for any help.
Pat
I should add I have Win 8

 

I believe that GPT under 64bit isn't supported until version 10.1. If that's your situation, you won't be able to use it until the next update.

 

Thanks, I guess I will have to wait.