I managed to:
- Fix the priorities, so sprites appear behind the foreground tiles. This was fairly simple -- I just had the priority numbers wrong. Which makes me wonder how it ever worked in the GBA version, but I didn't get around to comparing the codebases to find out why.
- Add black foreground borders around small dungeon rooms. Before that, it looked weird when you walked off a screen...you could see your character out in the limbo beyond the room as you exited. So now the black space around the outside of rooms is in the foreground. It was a pretty easy fix, as I took a random room tile, and just gave it an all-black palette, to avoid having to add a new tile.
- Fix a few other minor scrolling glitches
- Get the overworld tiles to load correctly. Like the priorities, I was doing this dead wrong, so it was an easy fix -- I was loading a fixed amount of tiles for each map, and that fixed amount was completely wrong.