The default behavior of a rectangular shape would be to move/resize only the side(s) that you are dragging. Have you converted this rectangle to a symbol? If so, that little white dot in the center of it is likely to dictate how it behaves on a resize. if you move that dot to the registration point, or to the side you do not want to have move, then it might behave more to your liking. I can honestly say I don't know what that dot is called or why it's around.
yes, it seems that Flash CC transform tool behavior is different from all previous versions.
The new behavior uses the Transformation point, which makes some sense in most cases.
It's of course very tedious to move manually this point to one side or another (moreover it seems that there is no natural snapping).
At first sight it seems that Adobe broke a valid and useful feature,... but finally I found this:
- If you want one side of the bounding rectangle to remain fixed, use ALT key.
- With pure drawing shapes, using CTRL key offers even more control (+ skew)