Im also using G25, without profiller, (just latest wingmanteam drivers) under XPHome, XP64 Vista and Win7, I have to admit Im not very good at drifting, but Ive experianced no problems with any of the Z testpatches.
Good luck, I hope the fresh copy of LFS will fix your issues.
I do make a point of re-calibrating my wheel & pedals, inside LFS when I start it, everytime.
SD.