"Actually you have it wrong. In waltz you want a swing action in the legs. first weight is lowered, next your leg moves in a swing action... her leg moves to make room for you, then your body weight follows. If you move your weight first then your feet you will run her over. try it"

No. The primary swing action is in the body, not in the legs. The body is in continued horizontal motion from the peak of rise of one measure down and back up to the peak of rise of the next, but the legs have to stop and start since you keep changing which foot is moving.

The only time the body stops traveling during swing-type movements is at the peak of rise. In something like foxtrot the peak of rise is lower and does not completely absorb the travel, so the body slows but does not stop on top.

That makes sence
Thank you

Anonymous. After getting it clear in your head what you personaly are trying to do . It might be a good idea if you then go to any of the demonstrations on youtube and see without any pre-conceived ideas exactly how it is done. If as you try to say the body moves first. Is this a forward movement, or is the body being lowered by the knees, which is a downward movement not a horizontal movement which then has the knees ahead of the rest of the body as Richard Gleave says, and pointed out by Terence. If you were to move your body forward first, how do you propose to bend your standing knee to an angle of 45 degrees. It is a fact that if I move my weight forward first I will find it almost impossible to bend my standing leg without my body pitching forrward. Some person might say that we are already lowered before we start.
Thats correct. And your knee will be the furthest part of you that is forward.
If you had Dance Vision 4 by Richard Gleave on a Natural Turn he calls the first step, Turn combined with Swing. Then Sway on beat three. He makes a point of saying that to Swing only on the first step is not enough. CBM will be missing.

"Is this a forward movement, or is the body being lowered by the knees, which is a downward movement not a horizontal movement"

Lowering is both a downward movement and a horizontal movement that occurs at the same time. When lowering from foot closure a beginner might be excused for not knowing about the horizontal part as it starts out small and only becomes large towards the completion of the lowering, but an advanced dancer must have this in their awareness. And the horizontal component should be obvious to everyone when lowering with the feet apart.

"If you were to move your body forward first, how do you propose to bend your standing knee to an angle of 45 degrees."

I would not, as doing so is pointedly absurd. An angle of 45 degrees in the knee would give you the appearance of someone trying to sit on his heels and do cossack kicks. I rather suspect you meant to write about something else, such as the angle of the shin relative to the floor? (though that would only reach 45 degrees in championship scale movement)

"It is a fact that if I move my weight forward first I will find it almost impossible to bend my standing leg without my body pitching forrward."

Only because you personally have not yet learned how to manage the trajectory of your body weight, and how to decouple that from your posture so that you can remain upright.

That you seem to want to be bending your standing leg at a point in time when you should be straightening it from its bent position doesn't help matters either.

Anonymous. I can see by your paragraph four that you have no idea how to bend your knees without sticking your rear out. With the 45 degree angle from the thigh to the knee will mean that there is also the same angle between the knee to the foot. If at this point you were on your toes you would also have that same angle between your toes to your heel. If anybody asks I can explain how to make a model from a strip of paper that shows exactly how the legs and feet are able to make these angles without their backside protuding. Bottom out, would be a sitting position wouldn't it. Very much like a Cossack Dancer.

"Anonymous. I can see by your paragraph four that you have no idea how to bend your knees without sticking your rear out. With the 45 degree angle from the thigh to the knee will mean that there is also the same angle between the knee to the foot."

You really need to find yourself a protractor, as if these angles you propose were actually the case, you would have lowered ridiculously far. Under your proposal, unless you simultaneously introduce foot rise it is a geometric fact that the thigh would be HORIZONTAL. Obviously this is not how it is done.

"Bottom out, would be a sitting position wouldn't it. Very much like a Cossack Dancer."

Which is to say totally out of place in a ballroom hold.