I was wondering the same thing. It does it to me every time I get to a new day(2nd or 3rd). I don't know how to get it to go away. Last time I got to the 2nd day and it went black until I walked through a passage to another area. I'm in town right now and the 3rd day is only seconds away. I wouldn't mind this as much if I knew a good way to get the game working properly again. Does anyone know?
It's a rom issue. The screen is supposed to get smaller I believe, which isn't supported in the port. It lasts for about 30 seconds on my computer and then just goes away. I think it won't do it if you're in a dungeon... may be wrong though.
Ok, well I guess I can just stand still until it is over. I was thinking I had to navigate through the darkness to find a door to go through(thinking that loading a new screen would fix it). Thanks for your reply.
Yes, the effect is that every time the clock tower rings, the screen shrinks one step. I'll take some photographs of it on my N64 later. It's pretty cool actually