First thanks to @LoboCNC for such a great design, and including the STEP file for an easy remix! The magnetic driver I'm using has a 0.39" diameter shaft, but another remix just has 4 steps in Fusion 360 (just adjust dimensions to fit your driver):
In my case, I actually made the hole 0.58" deep, as my bit's hex shaft doesn't extend very much.
I printed with a 0.6mm nozzle with 0.2mm layers in PLA. I did use supports everywhere, though I probably only needed supports from the build plate only.
The author remixed this model.
This remix allows the screw holder to be put on a magnetic hex driver extension, rather than just a hex drive bit. In this way you get the benefit of the magnet pulling on the screw head, along with the holder keeping the screw centered.