Hi Chri, for the z value one it would probably work best to do that in one of the elevation views rather than in the 3D view.

> Is there a way to lock dimension axis (x, y or z), then click
> on 2 points to create the dimension and a third point to place the result

There is a way to do that, if you make a construction line you can then activate "Project next point" onto it:



- Michael