No supports are needed, they are modeled in through the pillars. It is a single STL and you will have to do a color change inside of Prusaslicer or Cura and change the color mid print.
The marbles first enter a halfpipe where they leave by one of the two paths and descend down to the cross junction. They cross the junction and continue further to the funnel where they roll around for a while until exiting the module.
This module was designed by a fellow buyer/designer Luke H.
You are buying digital STL file available to download immediately after purchasing. You will need a 3D printer (13*13*13cm) to print it. This module fits on all of our marble machines that take modules.