The easiest way to handle "SDK" functions (like loading mods) is the Sonic Mania Mod Loader .

She clicked download. The progress bar didn’t crawl; it pulsed like a heartbeat.

The RSDKv5 decompilation, led by developers like Rubberduckycooly , allows the game to run on hardware it was never officially released for.

Backup Your Data: Never modify your game files without keeping a clean copy of the original Data.rsdk.

Are you looking to use or just the base Plus game?