How to replace sprites with an already existing id?

I’ve been trying to change the sprite of tiles that already have an existing id (for example “t_open_air” to “t_sand”) and somebody suggested this fix, however I’m kind of drowning in text and don’t know how to get it to work or which parts are necessary (I only want to change terrain textures)

Are there any current-gen (experimental ver) mods out there that force the game to change pre-existing tiles to a new fg, that I could use as a reference?
This is pretty much my one and only biggest roadblock in creating an overhaul mod, so it would be greatly appreciated if somebody could even just whip up a quick and simple example of how they changed a terrain tile (like if they changed the “t_dirt” to “t_sand” even) that already pre-exists as an id (e.g. its a unmodded terrain that already exists in game, not a new entity like secronom making “t_flesh” tiles)

I tried that but “t_open_air” still refuses to change into anything else

[
  {
    "type": "mod_tileset",
    "compatibility": [ "MSX++DeadPeopleEdition" ],
    "tiles-new": [
      {
        "file": "1_tiles_32x32_0-5199",
        "tiles": [
          { "id": "t_open_air", "fg": 3215 }
        ]
      }
    ]
  }
]

Am I missing anything in the code? is there anyway to force the game to change?

You are missing a sprite. Try using an image with a single sprite in it, not the file with thousand tiles in it.

still nothing.

[
  {
    "type": "mod_tileset",
    "compatibility": [ "MSX++DeadPeopleEdition" ],
    "tiles-new": [
      {
        "file": "changeair.png",
        "tiles": [
          { "id": "t_open_air", "fg": 2 }
        ]
      }
    ]
  }
]

This has baffled me for the past couple days. Would you or anybody else be able to see if you can do it on your end? it would mean the world to me for the mod i’m making

There was a similar topic I’ve posted in… My information in there might be a bit dated and I can’t verify if this little trick still works right now, but you could give it a try and report back:

Or, in short:

nope, still doesn’t work. I don’t know if a new update “broke” being able to force overide of terrain sprites, or i’m missing something incredibly stupid, but this thing just doesn’t seem to want to cooperate.
fortunately I have a backup plan to see if I can get what I want without trying to herd cats with the coding