Saved sessions on ONE route crashing Trainz

[FLWBStrainman]

Hi all, I have recently discovered a problem. For some reason or another, recently I have been unable to load saved sessions on one of my custom routes. Saved sessions load just fine, but I get a fatal error on startup. I have not written down exactly what the error says. I usually click "continue." If I do this, the game eventually crashes and locks up the computer... hard. First I usually notice the frame rates decreasing rapidly, until the game eventually freezes completely. Then the audio drops out. I am then stuck with a frozen computer. I can usually come out of it by logging off via task manager and logging back in. I almost had to do a hard-power-off recently. I have a generally good 'puter. Again, this only occurs on one route and only when trying to load saved sessions. It might help to know that the freezes ONLY occur on sessions saved after a particular surveyor save, and the fatal errors mention a faulty script of some kind. It seems to me that it would be difficult to find the offending object and delete it. Would it help to know the exact text in the fatal error? By the way, I am running Trainz 2006.

My computer specs:

Windows Vista Ultimate Edition, 64-bit (Service Pack 1)
2 GB RAM
ATI Radeon HD 3850 video card
AMD Athlon x64 X2 dual core processor 5000+
32-bit resolution