Horizontal scroller (rotation)

I’ve make an horizontal scroller for my thumbs (jpg are external). I apply a _rotation property -1 on my container. When i move the thumbs dragging the bar, the Images or box, do slightly jerkily up and down.

This is the example: **http://tinyurl.com/y9tdczx

**

I use actionscript 2. And for rotate the scroller i use:

thumbs._rotation = -1

Do you know how i can optimize this problem?

Thank you.