X Axis as Time

So the original question remains unanswered, the offset has nothing to do with the crosshair picking up the wrong values, it was coincidence that the offset seems to be a bout 12 hours in pixels. Please look at the original question 27 Feb at 4:06am

The X/Y charts support and date/time for line and marker were added afterwards and the initial design did not allow values to be painted with different XScales, Therefore we have introduced the XScaleOffset property which can be used to starting drawing at 0 or at XScale. We are unaware of any crosshair issues, but we will investigate what goes wrong here.