The original design is nice but I found the track height is 8.5 mm instead of 9 mm for my railway system causing all powered locomotives to stuck on it.
Since I had to adjust track height I changed all measures to fit user Smuk3D brio system as in the attached .pdf file.
I also made an additional smaller design for 2x2 stud brick.
Remixed from: https://www.thingiverse.com/thing:14175
Print Rite DIY
Printed in PLA with 3 perimeters and 4 top//bottom solid layers.
I would recommend adding some turns of brim and fan at 100%.
I had warping issues on corners even with the heated bed turned on.