I have no bloody idea how to change or rearrange tilemapped Mode 7 data. All that stuff is interleaved in the data itself; neither of the programs I used in this tutorial can change it.
The SNES has 64 KB of video RAM in two RAM chips. One stores the even-numbered bytes (0, 2, 4, ...) and the other stores the odd-numbered bytes. Normally they act as one continuous block of memory.
In Mode7 though the data from one chip is used for the tiles and the other one for the tilemap. So to separate the two you'd use only the even bytes for the tilemap and the odd bytes for the tile graphics.
Once it's untangled, the tilemap is simply an array of 128x128 bytes, each indicating one of the tiles. The tile data is an array of 256 bitmaps of 8x8 pixels each (not one single bitmap of 128x128 pixels as one might think).
Btw. games can store the data either separate or interleaved, and select accordingly how the VRAM address is incremented, so you might encounter both types.
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I didn't know you could use that combination of programs to make it work. Still an overcomplicated pain in the ass however you slice the turkey though.
I have a short fuse and get frustrated when something is a long cumbersome process, then the engineer inside me says: "What can I do to change this and make this go faster?". But of course, I'll be the first to admit, sometimes, it's still more efficient time wise to do the long process than create a new tool, especially if it's something you won't be doing often.