This is a small SNES game base. It has an embedded tilemap renderer, sprite system and a lot of other things.
To build this, you'll need snesgfx, tiled and piped-asm. All of this can be downloaded by running the ./update_deps.sh script.
To just build the output ROM, use make.
To make intermediate files for editing in Tiled, use make render_tiles; make render_blockdefs.
tl;dr: ./update_deps.sh && make
Good luck!
The chunk format is one byte per block, with metadata, which contains two pointers to block mappings. If the MSB of the block byte is set, it's pulled from the second pointer rather than the first one. The block mappings format is interlaced and contains all top left corner data first ($100 bytes), then top right, etc.
Levels are stored in the Tiled JSON format. Reloading the graphics and palette is up to the engine as of right now, but in the future it can be done using triggers within the chunk. The build script will automatically determine which block mappings to use, and in the future it would even be able to automatically generate block mappings from a single big set.