When I was clearing through the UBW route again today in order to get every scene, I get an error when I hit the scene "15th Day: Return home, night - before the final battle"
The scene shows up as a black screen when I go to it normally, and it just shows the skip scene background when I skip to it.
Below is a screenshot of the error. I have japanese text support, updated to the most recent.
I am using Windows Vista 32 bit with Service Pack 1. I am using the voice patch - I have not updated to hotfix 3.1 as I find the flow-chart in game to be useful. If this is caused by this, I can get rid of it. If further software or hardware details are necessary I will post them, or edit them in to this post.
edit: I checked a past save and I have a save point at this scene with the choice open. I am not able to load from it either. If I load it, it will open to the Shirou's room background and then skip back to the main menu.