Last night I used my downtime to play video games instead of working on Anguna. But tonight was back to work. I tackled some of the easier items this time.
Darkness/lanterns was easy: like blending, I just had to update register names from my GBA version. I also was using macros to do all the bitwise operations to write the registers, so I changed them into first class functions, which makes me feel less dirty. It worked the first try.
The black space in the backgrounds in caves had decided to be a rather ugly teal color, so that was the other thing that needed fixed. Another easy one...I had two different functions for applying the correct palette to backgrounds: one for dungeons, one for overworlds and caves. And I had only updated the dungeon one. Just needed to make a tiny update to the overworld one, and it was all good.
If only all changes could be this simple. (Actually, it's late and I'm tired, so I haven't tested these on hardware, but after that last mess I got into trusting my emulators, I won't guarantee that this was simple until I know it works on the hardware).