not a problem, I improve my english speaking
I will do an english exam on the 15th of June ;)
But in Carrara, you have no UV tool at all. Just predefined UVs, with no parameters, and after, you just can manually move the points of your UV map.
Move a gizmos don't move, modify, (or anything else) your mesh. It just creates UVs. Instead of the bounding box, who don't do anything on UVs, but just moves the object in the scene.
But indeed, if you still don't understand, I think you have to do another thing for a moment, and when you will be more skilled on 3D, and a little bit more familiar with UVs, I think you will understand later
