I used GameMaker many years ago on a much earlier version (and less featured), but this is my first attempt to jump in using GML language.
I never got the networking implemented, but this is a basic, and very true to the original Pacman game. Each ghost has a different chasing and scatter behavior. I also wanted to keep disk space low. So there is only one set of ghost animations tinted a different color. In fact, all sprites are white with a tint applied. So more CPU intensive and less memory intensive.