This is a rough split of an RM2k3 tileset, also called a chipset.
(A) is animated autotiles. I'll put the explanation of these lower down, as they're rather confusing.
(
is normal autotiles. These are laid out how they look, they're in the same layout as XP.
(C) is lower-layer tiles. These can have transparency, only 100% opaque and 100% transparent, and they can't have anything beneath them, so they will show through to the parallax layer. They're what you see on the lower tab. Tiles in
(D) are displayed above them.
(D) is upper-layer tiles. These can also have transparency, though with the same rules as
(C). The transparency color needs to be in every pixel of transparency, as 2k3 can't handle png transparency. These are the tiles on the upper tab, and are displayed above
(C).
(E) is the blank tile for the lower sheet. This would be what you'd use as an eraser for lower tiles. It should be set to X passability.
(F) is the blank tile for the upper sheet. It has the same purpose as
(E). However, it should be set to ☆ passability instead.
For all 2k3 tilesets, the sheet should never have transparency, and should always be indexed to 255 colors. It should also be exactly 480x256 pixels in size.
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This is a 2k3 animated autotile section. I believe it's correct, but I haven't worked with them much.
The center tile is, I believe, used by all three of the autotiles, but the pic is done and I don't want to fix it

. If you look at an autotile tutorial for vx ace along side this, it should make pretty decent sense.
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