Scrollbar seems to small for how much has to scroll, maybe can be revised/fixed?

Is not a bug, more a nuisance but indeed is a bit confusing because it has no logical/intuitive linking between scrollbar length and scrolling distance.
What do I mean by that?
Normally, a scrollbar should have its length proportional to how much it has to scroll (unless is too much to scroll, then is just locked to a small defined size).

General scrollbars behavior:

1. if all information is contained into the view area, the scrollbar button should be as tall as the window itself, or even grayed out (see internet browser windows behavior)
2. if there is another screen to scroll beside the viewing area, the scrollbar button should be half in size, to give a intuitive feeling about what's left out of sight.
3. if there is more to see, let's see three screens more, then the bar should be only one one quarter of total hight (because we have in total of 4 screens to see).
4. if the total quantity of information is so much that dividing the scrollbar button would end in a too small button, then the button is locked to a specific size, decided by who designed that interface, but basically that shows "there is plenty to scroll down".

Now, if we go back to PortableApps Launcher - the scrollbar button seems to be very small even if there is not that much to scroll down. As you will be able to see in the attachments, there are only two screens and just a bit more to scroll, but the button is so small like one would expect to have about 10 screens to scroll down.
Of course this won't impair the good functionality of the interface, but will impair the purpose of it: a comfortable user interaction. The sole purpose of graphical interfaces is to provide a friendly and intuitive mean for the user to interact with the app. Other than that, a text-based interface (a console) would suffice. My point is: if is a interface, could be made better.

Hoping this post will help improving the app, i am looking forward to see this aspect fixed.
Thank you very much.

Image link that describes the feature in discussion: http://i.imgur.com/NI2BqbX.png?1