Dynamic text scroller is choppy

Hey i made a text scroller and its too choppy is there a code wich i can enter into that makes smooth when i click a button or that keeps scrolling smoothly on rollover?

here is the code i am using for the up and donw button

on (press, release, keyPress “<Up>”) {
currentScroll = scrollableText.scroll;
if (Number(currentScroll)>1) {
scrollableText.scroll = currentScroll-1;
}
}

can i add somthing that would make the scroller scroll on rollover and scroll smooth? thnx in advanced