As now i know programming lua, so this is my first mod
download http://pastebin.com/MBtQrW6c
to install :
1)Open your PowderToy folder
2)create a new file and name it "autorun.lua"
3)Open it with notepad
4)Paste the code from the PasteBin Link
5)Start PowderToy
it adds a button and a menu that you can change particle type or the temp , like changing water to oil
PROP is already for dumbs.
PROP is easy to use.
Make a mod that lets you create new lua elements, ingame.