Overlay mod. (1 Viewer)

[Iago]

Hello, I'd like to add images to the game so that they overlay the characters and the background, something like the tree covering or the video camera mods I've seen in the forum. I've been searching for an explanation of how to do it, but when I find people talking about the subject in some thread they always seem to asume some previous knowledge that I lack (I stick to the templates and the tutorials when making mods and have little understanding of what the code actually does). I have even found a mod that loads overlayed backgrounds through a menu, but I need something you can load automatically with the dialogue or the character. I tried to decompile some of the mods, but they're far more sophisticated than what I intended to do and I only got more confused.

So the cuestion is: can someone please explain to me how can I do this? Do I use one of the loader templates as base? Do I code it from scratch?