No idea. I've never heard of such a problem before. I'd say make sure you have the latest video drivers for your card, and to also play with your DirectX accelleration settings, etc. The ReadMe included with the patch explains how to find the best settings for that in the 'video playback issues' section.
Oh, see if there is a LOG.TXT file in the YS1_WIN folder and paste the error reported. That might help troubleshoot if it's present.
