Internal is a set of natural body movements so it's a bit hard to brake down directly but I'll do my best.
First the body must be relaxed from head to toe, using no effort (by effort I mean no unnecessary muscular force to remain standing, <snip>
Kind of the opposite of the former. This means taking force into the body, and directing it back down into the ground. In reverse direction from before. taking the force into your body from what ever location (hand, head, shoulder, hip etc.) and directing it through your body via skeletal alignment and support muscles back into the ground.
First off, I hate to say it, but I'm pretty sure from the descrip that Chris just gave of producing force the "internal" way, he's pretty much way off base.
What was just described is more akin to "kinetic linking" say in the fashion that a boxer hits.
The second you initiate movement in your foot you should feel it in your hands. There's no delay.
Actually, scratch that, you should always feel "the ground" (in a metaphorical sense) in your hands. As in it's always there.
It's like your (and I'm stealing M. Sigmans imagery here) body is covered in a huge tight spiderman suit. Tugging on one part of the suit causes an instantenous reaction in the opposite end of the suit.
This is a physicl feeling and not some kind of metaphorical "oh if I visualize it this way it works better" thing.
As for rooting, that's way too vague. You could direct the force to the ground and simply "brace" with your leg but that isn't it either. In fact you can be "rooted" as you move