I've ceased construction of the main map of chapter 3 since KhanFusion already had done exactly what I was going to do, but instead I've started to develop more in-depth maps with extra details, using his work.
I'm working on adding a coordinate-system for chapter 3, using green lines to highlight secret paths and yellow lines for walls that will disappear later due to earthquakes, icons for Bell Guard items, coins and other artifacts and making separate files for the other maps instead of stacking them all in one image.
I'm also replacing some of the dark lit areas in KhanFusion's map with in-game footage, where Mi lights up the place she's standing in, making it slightly easier to get an idea of the layout of the room.