This is the source code used in my Custom Alts Mod (link: https://videogamemods.com/supersmashflash2/mods/custom-alts-mod/), in the form of .txts containing the code and a .txt explaining how to add it to a .swf yourself. This is for people with modded .swfs who want to include it in their mod/modpack.

Don't bother with this if you don't know what you're doing.

Enjoy!

Unpack the .zip and follow the instructions in TUTORIAL.txt