How could I use Egomoose's gravity controller with a custom rig

I’ve used it as it is and when I do I my character just flies through the ground, I’ve messed with the scripts a bit and nothing has changed. Has anyone figured out how?

I think you should contact EgoMoose about it, after all he is the creator of it.

Does the rig work normally without the gravity controller?
You may also want to post a video because “flies through the ground” is very vague.
I imagine:
The rig acts like it’s CanCollide off and just drops through the baseplate and dies (Rig Parts are CanCollide off).
The rig sinks up to a certain point (possibly Humanoid HipHeight issues).
If you’re using the gravity controller, is the “ground” you any Part that the rig is trying to walk on other than the baseplate?

As you can see, words sometimes have more than one meaning depending on how they are perceived by the writer and the reader.