Since Creo 3, on a drawing, when you select Dimension and then choose your first reference, a preview of the dimension is attached to the pointer. If you press CTRL to select additional references, the preview of the dimension updates, based on the selected references. But, the preview of the first reference stays visible and will be shown (almost) on top of the pointer and so it's hard to select a second reference. This is quite confusing; at first sight it's not always very clear which reference was chosen exactly.
It should be better to:
- Let the preview of the dimension disappear from the moment CTRL is pressed (and, of course, show the corresponding preview after the second reference was selected)
- dynamically update the preview when you hover over the new selection(s). (Altough, this might be a little bit too buzzy)