When designing an interface you may want to mix the use of scrollable areas with splitters. The advantage of that technique is that users can resize each column separately. Where should the splitters be placed to achieve that effect?
When displayed in the form editor, splitters should be placed on the right most edge of the scroll bar of each individual area. When adjusting splitters position, the placement should be very accurate otherwise they will not display properly. A positioning that is too much on the left will display a blank margin in the next column on the right. A positioning that is too much on the right will truncate the next column on the right.