So, here's the bag of plums

Whenever I boot up Garry's Mod to have hours of fun, I, like any other person like to use mods. But there's a problem with this mod especially

IT DOESN'T SHOW UP IN MY GAME, like.... at all!, not when I hold the ''C'' key, not in commands, there's no trace of either the ponies OR the editor in my game, I've downloaded the required addon (original PPM). but still nothing!

is there any fix to this?. I want my pony ;-;