Xara's Nudging and Grid do not seem to work hand in hand?

[Nostaw]

That isn't your grid point, what you are seeing is the object selection bound handle (blob). A grid point will not show that large at such high magnification.
You can colour the rectangle then add an 0.25pt line and see the grid point is on the line centre point. Seems to be dead on grid in my Designer Pro X9

Are you sure you turned the grid on ('Show Grid' or keyboard shortcut ".")? You can also turn the view quality to 0 and then check again. The Xara file I uploaded didn't use an outline color, just a solid fill. I checked with Xara Xara Prov8 on another machine and I can confirm this behaviour since at least version 6 on at least 3 different machines.


Please try the xara file attached:
move-8-left-8-down-zoom-in-25600percent.xar

You can make this more evident: Hold shift and press the cursor keys: 20xleft, 20xdown.
Select the Square and move it slightly, you should see it will snap back to the top left corner. It wouldn't snap if it was aligned already.