Control Object Properties
LoadPoint Insertion point for List/Drop box loads
    The 'LoadPoint property is a +PxPlus Exclusive (build 9182)
Description The LoadPoint property controls where the data loaded to a LIST_BOX, DROP_BOX, VARLIST_BOX, or VARDROP_BOX will be inserted.

When a list/drop box load directive is issued with no index the current contents of the control will first be cleared and the new data will replace it. Setting the 'LoadPoint property to a non-zero value alters this behaviour.

If 'Loadpoint is set to -1, the data included with the list/drop box load directive will be appended to the list box contents.

If 'LoadPoint is set to a value > 0, the data will be inserted into the list at the point specified and the value in 'LoadPoint will be reset.
*Note* A positive value in the LoadPoint property is reset to zero when a list/drop box LOAD directive is executed. A value of negative one (-1) which indicates 'append' is not reset by the load directive.
  This functionality allows drop boxes to be loaded a block of records at a time.
   
Used by DROP_BOX LIST_BOX LISTVIEW VARDROP_BOX VARLIST_BOX