Here are a couple potential fixes for the problem. If you are dealing with cursors on the graph, I would look into CursorChangeEvent, CursorMouseDown, CursorMouseUp, and CursorMouseMove. The ChangeEvent is triggered upon repositioning of the cursor. MouseDown triggers on the depression of a mouse button on a cursor, while MouseUp triggers on the button's release. MouseMove is triggered when the mouse is moved over a cursor. These each give X and Y positions in the arguments. If you used these and then made a Sanp to nearest point, you should have the coordinates before you sanpped to the point.