Missing rolling stock shapes/textures

[yerkes]

I'm running MSTS on XP with a Radeon 9000. Bits of my rolling stock seem to have disappeared lately (sorry, I can't recall file IDs for the following):

Mk 1: coach ends
Mk 2c: underframes + bogies
1938 stock: sides and roof

The only way I can get the textures to appear is to put train object textures settings down to the lowest setting - which is obviously far from ideal, especially when you look at the bits which do appear correctly. I've done the usual tweaks to the graphics card settings but without success.

I don't remember this ever happening before, and I can't think what might have triggered it off. Any suggestions? Thanks in advance.

PS Sorry if this is in the wrong forum.