We know that if one has used MMO cheat by building, by new installation of this lot must one set this lot in build mode within a plot - instead of installing it in the map of city.
But my surprise was that part of buy and build objects have lost their original position although after the right art of installation. In concrete, those objects are still there on the right floor position, but have lost their height position. The strange point is: not all the items which were built with MMO cheat have lost their height. I've asked myself why since long time.
Now, I think, I have found the answer.
Let we make a test: open a new empty lot. Build a room in this lot. Then put one vase outside on the floor and use cheat to increase it's height position three times. Now, the vase stands in the air. Put also a vase in the room on the floor. Use the same way to increase it's height. So long I have saved the lot and only load the game again, the position of the both vase aren't changed. But if I pack this lot into gallery and install it new in a build mode, now, the vase outside has lost it's height and loaded on the floor again. The vase in the room keeps it's position. This means that the free stand objects which not belong to a room will lost their height.

Currently, I only find one way to fix this problem. That is: to put the objects in a room.
For example, in my newly built lot have I put a hidden bench on a hill with MMO cheat, so that sims can sit on that hill.The huge stone (liberated stone from plasticbox) belongs to floor B1. The bench (downloaded from sims4fun) belongs to F1 and is heighted. Therefor, the huge stone dont't block the way to use the hiden bench. It's cool that the sims can sit so high, right? (see the first attached picture.)
After new istallation of this lot, the bench is fall down onto the ground of F1 because it is a free stand object. I can move camera near the huge stone to let the stone-look dissapeared, and, to find that bench. Then, I've built a room on the position where the bench was. Build entry (in this case stairs) so that sims can enter this room. Put the bench in this room and then increase It's height again. One can delete the walls of the room to let the lighting of the room like the lighting outside. But the area of the room should be closed. we can proof it by clicking this room. (see the second attached picture.)
If we see the wohle from far away, the room is hidden in the huge stone. We can see part of the bench. A lamp beside the bench belongs to F1 and is increased, too. The footprint of this lamp cross the wall of that hidden room. Done! Both the bench and the lamp keep their position even after a new installation of this lot. (see the third attached picture.)

In this case, I haven't found a solution yet:
I've put two seats (downloaded from mango sims) into the jeep (downloaded from sg5150), and raised them in a suitable height.
I can click the red seats to let sims sit in the car. So, I've got cool screenshot that the sims are using the car.
After the new installation of the lot, the seats land on the ground, beacause of the same reason. I don't want to build a basement under the jeep to fix this problem. What can I do? Perhaps I will let it and write in note of this not that one should heighten each seat 4 times by themselves. Or do you have an better idea to fix it?
I guess, if one make a new cc -- a car as love seat (the car seat should be higher as normal seat), it could help, herhaps.

an heightened item in basement whatever it belongs to a room or not will keep it's position after new installation of lot.