stack position and flicker

[rev at armbase.com]

Hi All
I have a stack with a collapse and expand buttons. She scripts of which are
similar.
Collapsing the stack is OK but if I expand the stack the top of it goes off the
screen if I move the collapsed screen near the top and press the expand button.

I fixed this with
on mouseUp
  put the top of stack Armbase into stacktop
  set the height of stack Armbase to 550

--now at this bit the stack is resized

  set the top of stack Armbase to stacktop

--at this point the stack top is reset so it doesn't go off the top of the
screen
--however, you can see this resizing and it looks like a flicker.

  hide button Expand
  show button Collapse
end mouseUp


Is there a way to prevent the screen from flickering. OS is WinXPSP2

Cheers
Bob