Control Rig - Basic Questions

Hi, I have just discovered this plugin and it looks really cool.

I have an IK system in normal Anim BP that follows certain transform. I would like to replace this system with the control rig.
For the life of me, I cannot figure out how can I feed a transform variable into the control rig node in the AnimBP. I can’t figure out how to cast any variable either into the control rig, since Control Rig doesn’t seem to have any variables.

That’s the first question. The second is, what can it be used for generally? I am basically making a first person mocap with Vive (it works actually pretty well), so I am thinking of using it for different transitions and procedural modifications of those animations. Maybe it’s used for something else completely?
I have read all the documentation, but just basic examples are present, like looking at an arm.