Nice work, I like how you've coded it clean like always, should help those who are beginners at gsc to get an idea.
Have you tried adding "level.disableweapondrop = true;" for only the zombies? Because I know if you were to add it to init, then there is no use for the option to drop weapons, so maybe try out putting it in for only the zombies? Like say when the player becomes a zombie, in add it there or would it not work? Not sure if it'd work and you've probably tried already but eh I stopped gsc awhile back so I would'nt have a clue anymore but it's good to play things like these on a rainy day i guess.
Cheers for the release bud