Hi, running on a 64 bit machine should not be a problem in itself - I've recently moved to a 64 bit Windows 8.1 machine.
Can I check what graphics driver you have installed, and if you've been able to run any other 3d software. One way of checking the driver is to run 'dxdiag' (from start, run). On the display tab, it should show information on the driver, and if direct3d acceleration is enabled.
James