problem re-installing X6 "Fatal Error"

cannot re-install X6 - I originally had it on a SSD drive (G) but it played up so when it stopped again, I tried to re-install X6 on main HD (C) but am having problems (it locks at 43% and asked me to OK a button - not sure what it is for) then once completed comes back with a Fatal Error message

using Windows 7 on a year old PC (It has been running up to the faulty SSD ok)

I think there may be some remnants of the old install left that is causing problem ?

can you please help.

thank, Ian