It seems to me, that you're problem is mine in blue - i use rotations, you use positions, in both cases we get those NaN values.
I think if we got a solution - the solution works for both.
Have you tried the advice Will gave me?
I'm sure if you calll getPosition and I call getRotation we will both get NaN's . I tried his suggestion, didnt work. I tried everything, calling getPosition on the enclosed geom, on the body, on the GeomTransform. Everything. Changing the order I calll methods, create the body before the GeomTransform, create it after, add Geomtransform to the body before I add the GeomBox to the GeomTransfrom and vice versa. I spent abount 8 hours trying different combinations.
According to the ODE docs it's very simple, so I just dont get it. Maybe it's because I use joint and jointAmotors to connect the bodies ? Should that cause any problems ?