I'll do that. Hey, one more thing. You know that background hack that let's you set a variable to determine the battle background? Does that work for all backgrounds? Because that would make everything even easier since I could just edit any background to any other one and call it in a script and save myself the trouble of all that.
Oh, palettes, yeah, that would also cause bad tiles. On the other thing, that you just need to repoint. Using GBA Graphics editor, you can insert the data (raws & new tilesets) anywhere (hopefully free space:p) and then just change the table to match your new location.
It's okay, I fixed them already. It was because a few spots on the palette map didn't have 2's over it. It looks awesome now!
There is a small issue though. You know that background where there are five different palettes linking to it, but they all use the same image and tilemap and stuff? If you change that background and the tilemap, it overwrites into nearby stuff and causes glitchy tiles to appear everywhere overtop the battle, which makes me think that they aren't safe to change, or can't be very extravagant without paying a hefty price. Just thought you should know.