Hi,

For the longest time, development on this game has been halted. So, upon request by a player, I have released the source of the game.

You can find it here: https://github.com/gurpreetsinghmatharoo/Rocket-League-2D-Source

You need GameMaker: Studio 1.4 to run it. If you need it for GMS2, let me know.

Cheers