Thank you for the review. In the story, backwards driving was a thing in the past nightmare races that racer4 did because they slipped into boredom and apathy, but that was all in the past. Now that you mention it though it could be fun to add it as a bonus feature you unlock after reading that dialogue. Also that is indeed JustinRPG's voice in the song, I sampled the sound from "riding moltres to goldenrod".
After some testing I also got the game to freeze when I initiated dialogue while moving around, I think that has to do with moving outside of the dialogue zone, thanks for letting me know of that bug.
Congratulations for finding the emerald. As for what the emeralds do, I tried taking inspiration from sonic the hedgehog 1 and made them do absolutely nothing.