In ClarisDraw 1.0v1, specifying a very fine grid and high zoom percentage may result in objects not properly snapping to the grid when dragged with the mouse. (The objects will probably snap properly when moved with the cursor keys.) You will see this especially if you have the Object Info palette open and are watching the object's position as you move it.
ClarisDraw 1.0v2 considerably improves object placement on the grid.