Try to update your 3DGS to the latest version and try again.
Maybe the version your using can't handle shaders properly.

You can download the latest update from the download page.

Good luck.

Windows XP SP3
Intel Dual Core CPU: E5200 @ 2.5GHz
4.00GB DDR3 Ram
ASUS P5G41T-M LX
PCIE x16 GeForce GTS 450 1Gb
SB Audigy 4
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