But if you are looking for a proper title, just say that this leg of the Amazing Marble Race is called the Everpath Underpass. Shout me out or something idk, but I would love it if you could go ahead and give this leg a go. Keep in mind that this race requires that the marbles have Collision Layers A and C to work with the conveyor belts, but you can change these if you need to match it with yours. Anyway, here it is. I gotta have the name Spero in the title, as you said.
Other things to note: the little dark green thing at the bottom right corner is only a logo. It's a minimalistic poison droplet with rays of light coming out, nothing too amazing artwise, but it is easy to make, so I put it somewhere on all my stuff.
Exposed yellow teleports the marbles back to the last unexposed yellow "dock". Pretty much a try-again for the section.
The bottom azure isn't just a high restitution block; it sends marbles to the right slightly in order to get them out of the area and back into the yellow box beneath the conveyor.
That should do it! Thanks for playing the submission (if you do). I provided some test marbles to see if it is something you would like to use. Destroy hoop with "1".
(Hey Jack, so I know you're pretty good at scripting stuff in Algodoo, and just wanted to let you know that extremely rarely, some marble may bounce to high speeds and phase through the two spinning things above the trampolines. Just wanted to let you know in advance; maybe you can help fix it if it ever happens while you use it. But onto that point -- if you feel like marbles are clogging into any section at all, because you usually find it happen at least once, then you have my permission to tweak the design to your needs so that marbles can flow through the course more smoothly (still give me credit though

))