This is puzzle box is quite a challenge to open, but easy to make. The required parts are 2 pen springs and a ball (3/8th inch or 8-10mm). I have printed this design and everything fits together well with 0.3mm of clearances on moving pieces. No supports are need!!!
Assembling the box is simple. To start glue the two springs into the "push" and "latch" pieces. Put them in their appropriate spots and place the ball in the maze. Next put a little bit of glue on the bottom of the post on the the "slide". Make sure that glue does not get on anything but inside the slot of the "push" piece. To finish it put glue into the groove at the top of the maze and install the "Front" and "Back" pieces.
I have included the Fusion file if you would like to make a maze of your own. I would love it if you post your makes and remixes!!!