I think I have discovered how Governmentman123 performs his magic tricks, but it takes some patience and a lot of hard work.
Maybe there is an easier way but the way I've theorized requires editing Scripts.img and Trigger.img; who here knows how to decompile lua language and codes?
I've taken a good look at scripts.img and there are codes that I can't edit but I clearly understand how they might function, such as spawning peds inside interiors, most of which are not listed in pedpop.dat.
Example code AreaSpawnPopulationData TRIGGER _SP_PREPHOUSE.DAT with some odd little characters in the middle of each phrase that I don't know.
Some one who knows lua, C++, and programming in general could do the trick after reading how the files work.
Correct me if I'm wrong and help me with this.