Hello I hope this still helps.
So annoying and so simple why not make ctrlA part of this ?
I finally found out how to move an ENTIRE model (mine is 3,7GB) on the terrain
I needed to set it over the created recessed terrain.
I still haven’t found out HOW to place an imported model exactly where I want it to be located
to move ALL select your model under the image
click on the tree buttons and SELECT ALL IMPORTED OBJECTS
then use the gyzmo to move it
take care NOT to click on the object as that will deselect the ALL !