I used a maze generator:
I made an 8x16 maze, which sets some basic physical limits on the size of the maze: 8 layers tall (plus one extra for a locking system), so now I know the maze will be 8 layers tall (with .125" material, that’s 1" tall) by 2".
I knew I wanted multiple tabs to keep things better aligned, and settled on three. That means that I needed 3 copies of the identical maze. That means the entire triple maze would be 6" wide, and so that sets the overall size of the box: it needs to have a 6" circumference. From there it’s just a matter of making your layers and keeping their order straight.
As for complicated, you can see from the pictures that it’s a true maze. This was the actual pattern:
Yup. Registration holes are essential. I use 1/16" brass rods usually. I’ve documented many projects like this, you can find them here:
It’s a new year, so I’ll tell you the trick.
Click if you want to know. It's probably simpler than you think.
This is a single layer (number 6, to be exact):
I’m not insane, I wouldn’t try to align those by hand.
This is similar to my heavily inlaid spindle box and my space invaders box.