Super Mod 4 allowed you to add your own code (and with that you could launch your own scripts) to run along with the mod. Also to add your own functions that go along with the selectors/spawners/etc.
Download:
Super Mod 4Just modify the SuperModCustom.lua file, compile it, and put it in the Scripts.img along with all the other files in the Advanced Install folder. (Make sure you only have one SuperModCustom.lur though)
Add another compiled script, (for example, you had a source LUA file called Cheese.lua and you compile it into Cheese.lur) you can use LaunchScript("Cheese.lua") to launch it. just add that in SuperModCustom. the comments in the file should tell you were it goes.
and if your source code (.lua) is a different name then your compiled code (.lur) I'm not 100% sure on which you put in launchscript. probably the source file, and i think if you use a hex editor you can see the name of the source file in the beginning.
Also I can't finish SM4 now because i lost the source code.