[zokemon]

Do you understand how .nw files work? Each tile bit can only be a number between 0 and 4095 which means there can only be 4096 possibilities. Extending the tileset would make it impossible to place the new tiles as they would just be modulated back to the beginning tiles.

You should also take note that the blocking/non-blocking tiles on the right of type 1 and the ones to the left of them are not the same. One is foreground and one is background.