Big thanks to Mauron for the help with CT compression!
Proof of concept:

Finally, CT decompression is done. As I said earlier, its quite modified version of LZSS. It is interesting to me that CT uses compression a lot. Even palettes were compressed.

SNES has so many variations of 8bpp ... Mode 3 one seems most used for static images like title screen. So what is Mode 3 8bpp - a planar (8 planes) format, where planes have specific for SNES order in the memory.
Mode 3 also support two extra 8bpp models - Direct Color and index. If you know a game that uses some of these 2 models, please share. Even better will be if you can make a zSNES save state of it :)