I am struggling with some strange graphical results:

One element in my model has been built with components x = 900 y = -900 Z = 0 (Z is vertical). However when I look at the graphical results, the model from this element down appears to have slipped down the Z axis and when I place the curser over the element to view the related data on screen I am given co-ordinates x=900, y = 0, Z=-900.

I have tried deleting this section of the model and rebuilding it but I still get the same error. Any ideas?? (Note we are still using C4.40 at this stage).