Reanimation when moving object using shape().left Powerpoint

I have discovered an unexpected behavior in powerpoint with reanimation of
custom animations.
I have a slide with a relatively involved custom animation timeline.
My application moves an object from Visual Basic using the .left parameter
(while the slide is displayed in slideshow window)

e.g.
shapes(myshape).left = x

when the object moves, the ENTIRE animation timeline reanimates (starts
over). this is undersirable. there are a couple of questions associated
with this i have been unable to resolve and wonder if anyone has any
suggestions?

1) i would like to understand WHY everything reanimates

2) i would like to be able to block all reanimation foro the entire timeline

3) it would be nice to be able to take advantage of this behavior at times
by allowing the reanimation for ONLY the object that was moved....or
alternatively....for everything AFTER the object's animation in the timeline

4) i have not yet figured out how to execute (or re-execute) an animatin
manually from visual basic....setting the animation for an object from VB is
one thing....but then executing it on command from VB seems a mystery

any suggestions?

thanks!