Cakewalk Sonar Power Studio 66 Firewire Drivers

My set up is a dell Optiplex 745 Windows 7 64bit with the audio interface Cakewalk SPS 66
This worked fine until I had a bit of a pc meltdown and was forced to re install Windows 7.
When I hooked up the SP 66 to the firewire - the blue pwr light comes on but when it comes to installing the SP 66 Windows 7 64bit driver, when it reaches the point where you are instructed to hook up the interface and switch on , there's a few rumblings in the hard drive but that's it. It gets stuck at that point and does not complete the installation.
I've tried many different Firewire drivers - including the Legacy driver which many people have stated cures this kind of issue. But not mine.
So I'm stuck with an audio interface that clearly powers up but this is not recognised by the SP 66 driver and am at the point of ditching the Sp 66 and going for a USB interface.  But it's frustrating as this could be something really simple and can probably only be sorted out by someone who has experienced a very similar problem.  This is beyond the pc repair people who are only interested in loading drivers but cannot work out why the drivers are not installing.
So any assistance would be much appreciated.

Thanks
 
Tried to install the  Edirol driver but it gets stuck during the installation at the same point - 
 
Ready to install driver
 
Please connect the FA-66 to you computer and turn on the power of the FA-66 (or SPS 66 with the cakewalk driver)
 
So I connect the audio interface as instructed, switch it on (power light comes on) and then nothing happens.  That part of the installation process stalls and does not move onto 'Next'.
 
So am thinking there must be some critical bit of info that the driver install of the SPS 66 is missing when it is connected - so might this be to do with the firewire driver or bus routing in the motherboard?  I'm lost..!