Dan...I restored to a point prior to my insatalling BVE4 to the Vista HDD, so at the moment, it's not there! Will PM the log extracts shortly. Many thanks, Dan.
(Some hours later). I reinstalled BVE4...that's all, no Uchibo10 or any other train, folder, etc, then tried to open. Got the display resolution box, then BVE4 has stopped working. I then did exactly what you earlier suggested with the two dx..vb.dll files. Still no good. I then unregistered the mscomm32.ocx file...still no joy. I had to power off for a period, then rebooted and BVE4 suddenly opened fine. Obviously, the reboot did something. If you ever revise your "tutorial" above, it might be an idea to mention the reboot. (Actually, it may have worked after the reg/unreg of the .dll files if I had rebooted at that stage! We'll never know. Many thanks for all your trouble, Dan. It is appreciated. Now to load some files and play trains again!
(Some days later) Unfortunately, things are not as rosy as it seemed. The problem has obviously shifted to what seems like the well-documented nVIDIA problem. BVE4 now opens, as I earlier reported, but after loading a few routes and trains, when it opens I get sound (so it's obviously running) but a white screen. Found a brand new driver for my card, but it made no difference. Has anyone actually found an earlier driver for the nVIDIA 7xxx card that fixes the Vista-BVE4-nVIDIA compatibility prob?