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Sprite Mappings Format - Sonic Crackers:

Sprite mappings define how the various 8x8 pixel tiles are arranged within a sprite, and follows this format:

SS - YY - TTTT - XX - ZZ

SS:
The size and shape of the sprite piece. 8x8 tiles are read from the VRAM and placed into differently-shaped rectangles:

SS = 00	SS = 01	SS = 02	SS = 03	SS = 04	SS = 05	SS = 0F
1	1 2	1 2 3	1 2 3 4	1 2	1 3 2 4	1 5 9 13 2 6 10 14 3 7 11 15 4 8 12 16

It's easy to see what sizes 06-0E look like, and 0F is the largest sprite piece you can use.

YY:
The position of the sprite piece on the y-axis. YY increases as you move an item towards the bottom of the screen.

TTTT:
This controls which tiles in the VRAM are to be read. Normally, 0000 is the first tile of the sprite you're dealing with.

XX:
The position of the sprite piece on the x-axis. XX increases as you move an item towards the right-hand-side of the screen.

ZZ:
Defines whether there are additional pieces of sprite in the current frame of animation or not. 00 tells the game to assume the next mappings block is part of the same sprite frame. FF tells the game to end the current sprite frame and start a new one.

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Pattern Load Cues - Sonic Crackers:

QQQQ - 9704 - RRR0 - D380 - FFFF

QQQQ:
Number of tiles to read from the ROM where:

1000 = 1 tile
2000 = 2 tiles
0001 = 10 tiles
1001 = 11 tiles
1002 = 21 tiles

RRR:
Where to start reading tiles from in the ROM, where 000 is the first of Sonic's tiles in the ROM; 001 is the second etc.

The purpose of all the other bytes is unknown.

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If there's anything about mappings you don't understand, the best thing to do is open a savestate in Tile Layer Pro, and open the ROM in a hex editor, and try to work out how everything works by yourself.