(End of) 2020 Update: Uh, it seems some time between now and when I wrote the text below, these games are working again? Scratch can be such a volatile platform :P Well, looks like Scratch 3.0 broke all my games that use this style of collision detection. Welp. Arrow keys to drive. That's it.
I found this in my unshared projects, so I decided to share it. It's an updated version of my project "Toad's Turnpike", which can be seen here: http://scratch.mit.edu/projects/2340978/. It's been updated to match the 2 newer ones I made after it, Baby Park and Sherbet Land.