A scroll bar increment. Specifies the amount of movement along the scroll bar when the scale on either side of the thumb is clicked.
A non-negative number (longint) (DEFAULT = 10)
The usable scrolling range of a scroll bar is from -32,768 to 32,767. A WdgLargeIncrement outside this range will produce unpredictable results.
WdgMaxValue, WdgMinValue, WdgSmallIncrement