Thanks for answering. This is the very problem in the first place: transforming the objects after they are imported. I wonder how do you or other users manage to transform (move/rotate/scale) objects in WED the right way? You or anyone else please, tell me so I follow the same procedure.
Here's a fact:
I have 2 256 x 256 cubes just by each other, laying on the ground.
If I scale one of them a little, it lifts from the ground and won't touch the other cube anymore, cause it shrinks by the cube origin (center). How can I move it after scaling, so it's again aligned with the ground and the other cube? How do you do it? I'm not that picky to ask for a possibility to edit the origin of an object, although...