Claudio's scroller

can someone please tell me how to adjust Claudio’s scrollbar height… when I adjust it manually and press the down button the dragger does not stop where it should but when i drag the dragger it stops where it should, any ideas??

Here’s the fla that Claudio post some time ago…

:link:

Do anybody knows a way of making the dragger MC to make an effect like this:http://www.exopolis.com/site/
Take a look at the ABOUT section, on the dragger of the text field.

I´d like an effect like trails and found this site. How can we do something similar?