BF2S Forums S.T.A.L.K.E.R Clear Sky Graphics Reboot?

Installed S.T.A.L.K.E.R Clear Sky today again, put the graphics near to full (I'm direct x 9).

And now I get error screens saying my graphics are too high so I can't start the game up.
Is there any way of entering the console and changing the graphics without going to the in-game loading screen?

Or shall I give up and re-install.

Thanks!