How do I make unbounded scrolling limited?

Hi there! I tried to google this, but with no luck.

So, what i need is: dynamically create unlimited amount of objects, one under another, by pressing "button", then i want to scroll up and down (like forum posts). I turned on "unbounded scrolling" and it worked fine, except i need to limit that scrolling by existing objects (one on top and one on bottom). Any ideas?

Find out the combined height of all of your stacked objects, then every tick set the Y-scroll(Scroll to Y in System object) to something along the lines of:

clamp(scrolly, 0, CombinedHeight)[/code:2ad69kcr]  
This will set the Y-scroll to its current value bounded by 0 and the combined height of your objects.  

Ideally, this should be the last action in your event sheet so that prior events which change the Y-scroll don't override your bounding.

Thank you very much! Will do this when i get home.