TheJoy

All the information you need to build in the world editor is on this web page https://3dxmodz.com/index.php?/topic/86-world-editor/ If you have built small objects, without wanting to change the scale and to be even more precise, you can still use the zoom of the camera with the cursor by clicking on the button "camera"

Try shift + C

As long as I can remember, hanging with space bar or shift + space bar has always worked with the pivot point of an object.

Nope, The pivot point of the sphere is not in the center of gravity of the object. But at the base of the object. Do not confuse the pivot point of the object (grid anchor point with the center point). If you want to center a sphere at point 0, you will have to create 1 1/8 of a sphere and make 8 symetries in pivot snap leng = 1