I love how you made all these files perfect for printing, without having to rotate or scale anything and without support. A true engineer!
I had to file down some parts, especially to get the lid in and out. The last 5mm is not very smooth, even after filing; I'm not sure why it gets stuck, but I suspect it's the inner shaft that is too tight at the top end.
(3mm PLA, 0,1mm layer height)
Also filled up the triangle/arrow holes with white, using a piece of filament and a soldering iron. See last picture.