How does a tileset.json read a tileset png?

So I made a tileset for a mod I’m making, but I have some confusions.

  1. How does the json file read the png, cuz its skipping the first tile that I’ve set?

I needed to set 1st sprite as "0" instead of "1". But i'd still like some info if anyone has it.

  1. How do I make it that the sprite turns with character? The sprite stays in default position (facing right) even if the @ turns left.

I set sprites as bg hoping they would appear behind other ones. But that just locks the sprite.

  1. Since I can’t currently buy aesprite, I just made it with paint.net.

Here’s the tileset.

Eldritch_BioArmor_normal

EDIT: Ok, so I solved both of these problems. Instead, how do I set layers, such that 1 mutation sprite is under a 2nd one?

Ok, I’ve figured it out. Needed to make a mutation_ordering.json based on the in game one.