How do I make my own or edit UIs?

Not just battle UI, I'de like to know how to make or edit the menu screen, the save screen, etc. What script section do I have to look up?

If I remember correctly, for just editing the look of each one you can simply go into Graphics > Pictures and usually what you want is in there to edit, if you're wanting to custom make/animate etc then I'm afraid I'm not as read up on it.

There is a tuorial by Marin. That taught me how to create your own.
https://www.pokecommunity.com/showthread.php?t=396842

If you want to modify existing ones you have to look at the corresponding script section. They are all named (usually starting with "PScreen"). The rest is up to you to figure out

Thanks! That's exactly what I was looking for.