Camera Tween not working

I downloaded this thing 3 different times…

It’s in my addons folder as instructed, but the last time I downloaded it, it was showing up in the tools menu under RENDER, but now, it doesnt even show up!

Is there something else I should be doing? If not, can anyone suggestion a camera manipulation tool similar to this, the goal here is to make GMOD movies…

THANKS

catmull-rom cinematic cameras http://www.garrysmod.org/downloads/?a=view&id=56328