Thanks Shane!
I have reinstalled trainz and Marias Pass X. I also downloaded the latest NVidea drivers (ASUS GTX550 TI).
No video settings seem to help except for John's suggestion for turning off Texture Compression and recommitting. Thank you, Shane, for helping me narrow down what I needed to do. I'm further chunking the work by category.
BTW, one of your other posts mentions a tutorial. How do I get to it?
-- Glenn