Now guess the background layers!
Note: If you want to change the background (i.e. use a different pattern), remember to first install Python 3, install the colour library with
pip install colour
It will generate a file named HdmaTable.asm. Copy its content into the level file but make sure you replace the old table i.e. remove everything below MaskingTable: (including that line) and then paste the new table.
I will include an easier insertion method once I submit.