How to put Cut-ins on Stepmania 5?

So i have the random movies folder and songs and stuff but i still don't know how to add cut ins. To me they make the game look pretty cool but i don't know how to script it in and i don't really see a forum on this so please help me.

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for clarification, movies meaning bgm's.
would you mean specific movies to a song, random bgm's to songs in general or something else entirely.

If I don't mistake, cut-ins in Stepmania are custom "Toasty" easter egg, so you need to edit a theme to implement them.

-Post #2
I Have the RandomMovies Folder by itself and I have the stepmania5 options set to cycle through the RandomMovies Folder randomly not set to any specific song.

-Post #3
and yes how would i do that and where do i find the toasty easter egg?

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