I'm trying to create a new elixir to add to the game, and I seem to have hit a bit of a wall. I've been studying the tutorials, and using SimsMX's mod(s) as reference, but I can't figure out how to get ingredients and skill level requirements added in, and I'm also not sure how to add the tuning to make the death type random.

Any help would be greatly appreciated.

Well I don't know much about, like you I too am still learning. But killing of a sim happens with a code like this
sim.Kill(SimDescription.DeathType.Burn);
where sim is an object of Sim.

I think you'll have to make it xml tunable if you want random death type.

Or maybe you can try this
Random rnd = new Random();
int num = rnd.Next(1, 13); // 1 <= num < 13
if(num==1)
{
sim.Kill(SimDescription.DeathType.Burn);
}
else if(num==2)
{
sim.Kill(SimDescription.DeathType.starve)
}
.
.
.
and so on....
Ofcourse I'm a newbie mod learner so I don't know if it'll work for sure but the logic is making sense to me kinda.

Hope I helped. And hope someone more experienced will help you.
;

Thanks. I'll have to try to read the script tuning tutorial again. Hopefully without going cross-eyed. Sorry for the delayed response.